a man has a mass of 70kg. Calculate his weight on earth where the gravitational strength is 10 N/kg
Answer:
So the weight of the body is 700N
Explanation:
mass of the object=70kg
force of gravity=10N/kg
weight of the object=w-?
as we know that
weight=mass × force of gravity
weight=70kg × 10N/kg
WEIGHT OF THE BODY=700N
I HOPE IT WILL HELP YOU
GOOD LUCK FOR THE ASSIGNMENT
The correct answer is 700 N.
Object mass = 70 kg
Gravity = 10N / kg
Weight = Mass x Gravity
Weight = 70kg x 10N / kg
Weight = 700 N
What is the gravity for a mass of 10kg?Mass is more basic because it is a unique property of the object. Weight varies from place to place depending on the acceleration of gravity. If the mass on the earth is m = 10kg, the weight is W = mg = 10 x 10 = 100N.
The strength of the Earth's gravitational field is 10 Newtons (N / kg) per kilogram. This means that there is a force of 10 Newtons per kilogram on Earth. Mass is the amount of substance that makes up an object.
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A child’s toy launches a model parachutist of mass 0.40 kg vertically upwards. The model parachutist reaches a maximum height of 8.5 m. Calculate a) the gravitational potential energy gained by the model parachutes, b) the minimum possible speed with which the model parachutist was launched. c) In practice, the launch speed must be greater than the value calculated in (b). Explain why? *
Answer:
(a) =34.0J
(b) = 13.038m/s
(c) =
Explanation:
(a) mass (m) =0.45kg
Height(h) =8.5m
Gravity (g) =10m/s^2
But P. E (Potential Energy) = mass × gravity × height
P. E = 0.45×10×8.5
P. E = 34.0J
(b) using v^2=u^2 - 2gs
Where v = final velocity
u= initial velocity
g = gravity
s =distance
But at maximum height v =0
0^2= u^2 - 2gs
Transpose u^2 we have
u^2 = 2gs
u^2 = 2×10×8.5
u^2 = 170
u = square root of 170
u = 13.038m/s
define hardware.Give 2 examples
Answer:
They are the physical parts of a computer.
examples :monitor,keyboard,system unit and mouse.
The displacement from equilibrium of an oscillating weight suspended by a spring and subject to the damping effect of friction is given by y(t) = 2e−t cos 4t, where y is the displacement (in centimeters) and t is the time (in seconds). Find the displacement when t = 0, t = 1 4 , and t = 1 2 . (Round your answers to two decimal places.)
Note that the correct times are t = 0, t = 1/4, t = 1/2. You can tell from the spaces between the two digits. i.e 1&4 and 1&2
Answer:
y(0) = 2.00 cm
y(1/4) = 1.56 cm
y(1/2) = 1.21 cm
Explanation:
This is a very simple exercise, the displacement of the oscillating weight from equilibrium has already been modeled by the equation:
[tex]y(t) = 2e^{-t} cos 4t[/tex]
Where y = displacement ( in cm)
and t = time (in seconds)
The task is to find the displacement when t = 0, 1/4 and 1/2
When t = 0 s
[tex]y(0) = 2e^{0} cos 4(0)\\y(0) = 2* 1*1\\y(0) = 2.00 cm[/tex]
When t = 1/4 s
[tex]y(1/4) = 2e^{-1/4} cos 4(1/4)\\y(14) = 2e^{-1/4} cos (1)\\y(1/4) = 1.56 cm[/tex]
When t = 1/2
[tex]y(1/2) = 2e^{-1/2} cos 4(1/2)\\y(14) = 2e^{-1/2} cos (2)\\y(1/2) = 1.21 cm[/tex]
The fielder attempts to catch a second ball. Just before the fielder catches the ball, the air resistance acting on the ball is 1.2N. Calculate the resultant force acting on the ball. Remember to include its direction and the unit. Assume the ball is falling vertically
Answer:
Resultant force = (1.2 - 9.8m)ĵ N
where m = mass of the ball
Magnitude of the resultant force = (9.8m - 1.2) N
Since the weight of the ball is expected to exceed the air resistance (because the ball is falling vertically downwards), the direction of the resultant force is vertically downwards. Its unit is Newtons, the SI unit of Force.
Explanation:
If a ball is falling vertically downwards, the only two forces acting on the ball include the weight of the ball (the pull of gravity on the ball) and the air resistance on the ball.
Weight of the ball acts downwards and is given as mg. where m = mass of the ball and g is the acceleration due to gravity = 9.8 m/s²
W = mg = (9.8m) N
In vector form, W = (-9.8mĵ) N
The air resistance on the ball = 1.2 N, the air resistance acts in the direction opposite the motion of the ball, and since the ball is moving vertically downwards, the air resistance acts vertically upwards.
In vector form, the air resistance = (1.2ĵ) N
Hence, the resultant force acting on the ball is the vector sum of all the forces acting on the ball.
Resultant force = (-9.8mĵ) + (1.2ĵ)
= (1.2 - 9.8m)ĵ N
Since the weight of the ball is expected to exceed the air resistance (because the ball is falling vertically downwards), the direction of the resultant force is vertically downwards.
Hope this Helps!!!
An electric dipole of dipole moment 'p' is placed in the position of stable equilibrium in a uniform field of intensity 'E'. The torque required to rotate, when the dipole makes an angle Ө with the initial position is pE cos Ө pE sin Ө p cos Ө p tan Ө
Answer:
Torque by electric dipole = pEcos thita
An aluminum bar 600mm long, with diameter 40mm long has a hole drilled in the center of the bar.The hole is 30mm in diameter and is 100mm long. If modulus of elasticity for the aluminum is 85GN/m2.Calculate the total contraction on the bar due to a compressive load in 180KN
Answer:
Total contraction on the Bar = 1.22786 mm
Explanation:
Given that:
Total Length for aluminum bar = 600 mm
Diameter for aluminum bar = 40 mm
Hole diameter = 30 mm
Hole length = 100 mm
elasticity for the aluminum is 85GN/m² = 85 × 10³ N/mm²
compressive load P = 180 KN = 180 × 10³ N
Calculate the total contraction on the bar = ???
The relation used in calculating the contraction on the bar is:
[tex]\delta L = \dfrac{P *L }{A*E}[/tex]
The relation used in calculating the total contraction on the bar can be expressed as :
Total contraction in the Bar = (contraction in part of bar without hole + contraction in part of bar with hole)
i.e
Total contraction on the Bar = [tex]\dfrac{P *L_1 }{A_1*E} + \dfrac{P *L_2 }{A_2 *E}[/tex]
Let's find the area of cross section without the hole and with the hole
Area of cross section without the hole is :
Using A = πd²/4
A = π (40)²/4
A = 1256.64 mm²
Area of cross section with the hole is :
A = π (40²-30²)/4
A = 549.78 mm²
Total contraction on the Bar = [tex]\dfrac{P *L_1 }{A_1*E} + \dfrac{P *L_2 }{A_2 *E}[/tex]
Total contraction on the Bar = [tex]\dfrac{180 *10^3 \N }{85*10^3 \ N/mm^2} [\dfrac{500}{1256.64}+ \dfrac{100}{549.78}][/tex]
Total contraction on the Bar = 2.117( 0.398 + 0.182)
Total contraction on the Bar = 2.117*(0.58)
Total contraction on the Bar = 1.22786 mm
A radioactive isotope has a half-life of 2 hours. If a sample of the element contains 600,000 radioactive nuclei at 12 noon, how many radioactive nuclei would be left at 6 pm?
Answer: There will be 75258 nuclei left at 6 pm.
Explanation:
a) half-life of the radioactive substance:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
[tex]t_{\frac{1}{2}}=\frac{0.69}{k}[/tex]
[tex]k=\frac{0.69}{t_{\frac{1}{2}}}=\frac{0.693}{2hours}=0.346hours^{-1}[/tex]
b) Expression for rate law for first order kinetics is given by:
[tex]A=A_0e^{-kt}[/tex]
where,
k = rate constant
t = time for decomposition = 6 hours ( from 12 noon to 6 pm)
A = activity at time t = ?
[tex]A_0[/tex] = initial activity = 600, 000
[tex]A=600000\times e^{-0.346\times 6}[/tex]
[tex]A=75258[/tex]
Thus there will be 75258 nuclei left at 6 pm.
Transverse waves on a string have wave speed v=8.00 m/s, amplitude A=0.0700m, and direction, and at t=0 the x-0 end of the wavelength -0.320m. The waves travel in the -x string has its maximum upward displacement. a) Find the frequency, period and wave number of these waves b) Write a wave function describing the wave c) Find the transverse displacement of a particle at x=0.360m at time t=0.150 d) How much time must elapse from the instant in part (c) until the particle at x-0.360 m next has maximum upward displacement?
Answer:
a. frequency = 25 Hz, period = 0.04 s , wave number = 19.63 rad/m
b. y = (0.0700 m)sin[(19.63 rad/m)x - (157.08 rad/s)t]
c. 0.0496 m
d. 0.03 s
Explanation:
a. Frequency, f = v/λ where v = wave speed = 8.00 m/s and λ = wavelength = 0.320 m
f = v/λ = 8.00 m/s ÷ 0.320 m = 25 Hz
Period, T = 1/f = 1/25 = 0.04 s
Wave number k = 2π/λ = 2π/0.320 m = 19.63 rad-m⁻¹
b. Using y = Asin(kx - ωt) the equation of a wave
where y = displacement of the wave, A = amplitude of wave = 0.0700 m and ω = angular speed of wave = 2π/T = 2π/0.04 s = 157.08 rad/s
Substituting the variables into y, we have
y = (0.0700 m)sin[(19.63 rad/m)x - (157.08 rad/s)t]
c. When x = 0.360 m and t = 0.150 s, we substitute these into y to obtain
y = (0.0700 m)sin[(19.63 rad/m)x - (157.08 rad/s)t]
y = (0.0700 m)sin[(19.63 rad/m × 0.360 m) - (157.08 rad/s × 0.150 s)]
y = (0.0700 m)sin[(7.0668 rad) - (23.562 rad)]
y = (0.0700 m)sin[-16.4952 rad]
y = (0.0700 m) × 0.7084
y = 0.0496 m
d. For the particle at x = 0.360 m to reach its next maximum displacement, y = 0.0700 m at time t. So,
y = (0.0700 m)sin[(19.63 rad/m)x - (157.08 rad/s)t]
0.0700 m = (0.0700 m)sin[(19.63 rad/m × 0.360 m) - (157.08 rad/s)t]
0.0700 m = (0.0700 m)sin[(7.0668 rad - (157.08 rad/s)t]
Dividing through by 0.0700 m, we have
1 = sin[(7.0668 rad - (157.08 rad/s)t]
sin⁻¹(1) = 7.0668 rad - (157.08 rad/s)t
π/2 = 7.0668 rad - (157.08 rad/s)t
π/2 - 7.0668 rad = - (157.08 rad/s)t
-5.496 rad = - (157.08 rad/s)t
t = -5.496 rad/(-157.08 rad/s) = 0.03 s
The frequency of the wave is 25 Hz, the period is 0.04 s, and the wave number of the given wave is 19.63 rad/m.
(A) Frequency of the wave,
[tex]\bold {f = \dfrac v{\lambda}}[/tex]
where
v - speed = 8.00 m/s
λ - wavelength = 0.320 m
[tex]\bold {f = \dfrac {8.0 m/s }{0.32\ m} = 25\ Hz}[/tex]
Period of the wave,
[tex]\bold {T = \dfrac 1f = \dfrac 1{25 } = 0.04\ s }[/tex]
Wave number of the wave,
[tex]\bold {k = \dfrac {2\pi }{\lambda} = \dfrac {2\pi }{0.320} = 19.63\ rad\ m^{-1}}[/tex]
(B)
Wave function equation of a wave,
y = A sin (kx - ωt)
where
y - displacement of the wave
A = amplitude = 0.0700 m
ω = angular speed = 2π/T = 2π/0.04 s = 157.08 rad/s
Put the values in the formula,
y = (0.0700 m)sin[(19.63 rad/m)x - (157.08 rad/s)t]
(C) When x = 0.360 m and t = 0.150 s,
y = (0.0700 m)sin[(19.63 rad/m × 0.360 m) - (157.08 rad/s × 0.150 s)]
y = 0.0496 m
Therefore, the frequency of the wave is 25 Hz, the period is 0.04 s, and the wave number of the given wave is 19.63 rad/m.
To know more about waves,
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Question 20 of 31
1 Point
Which of the following best describes what happens to valence electrons in
an ionic bond?
A. Valence electrons are transferred from a nonmetal to a metal.
B. Valence electrons are shared among many atoms in a lattice.
O C. Valence electrons are transferred from a metal to a nonmetal.
D. Valence electrons are shared between two atoms.
Answer:
C: Valence electrons are transferred from a metal to a nonmetal
Explanation:
In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.
hope this was helpful :)
Nabil wants to work out the density of a pebble. he has a displacement can and a beaker. What other piece of equipment will he need
Answer:
1) Measuring cylinder
2) Top Pan Balance
Explanation:
To find the density of the pebble Nabil should first accurately measure the mass of the pebble using the top pan balance
He should then fill the displacement can till the water reaches the outlet pipe at the to of the cylinder
He should then place the pebble into the cylinder carefully ans allow the water that would start coming out to stop
The volume of water in the displaced cylinder is then measured and the density is found by dividing the mass of the pebble by the volume of water in the measuring cylinder
[tex]Density \ of \ pebble = \dfrac{Pebble \ mass}{Volume \ of \ water \ in\ the \ measuring \ cylinder} = \dfrac{Pebble \ mass}{Water \ volume \ displaced}[/tex]
Please i need the answers now. a) Explain why i) More thermal energy is required to raise the temperature of 2 Kg of a substance by 10°C than is required to raise the temperature of 1 Kg of the same substance by 10°C. ii) A solid expand when heated.
Answer: find the answer in the explanation
Explanation:
1.) More thermal energy will be required to raise the temperature of 2 Kg of a substance by 10°C than is required to raise the temperature of 1 Kg of the same substance by 10°C.
Because the thermal energy depends on the mass of an object.
If the two materials are the same, then they will have the same specific heat capacity. Thermal energy can be expressed as:
H = MCØ
Where
M = mass of the body
C = specific heat capacity
Ø = change in temperature
H = thermal energy
If u substitute the two values of masses into the formula above, then, the mass of 2kg will produce higher thermal energy .
Il.) Heat causes expansion. Using kinetic theory to explain this, the molecules of solid material are in a fixed pattern, held together with strong bonds. When heat is applied to the solid, the molecules will start vibrating in their fixed position. As a result of this, the bond between the molecules begins to loss. This eventually lead to expansion of solid.
A wave has a frequency of 450 Hz and a wavelength of 0.52 m. What is the speed of the wave?
Answer:
Explanation:
ave speed is always (frequency) x (wavelength)
Speed = (450 /sec) x (0.52 m)
= 234 m/sec .
The density of pine is generally about 0.5 g/cm3. What is the mass of a 800 cm3 piece of pine
Answer:
400grams
Explanation:
Mass is density × volume
0.5×800= 400 grams
Mass is density × volume
0.5×800= 400 grams.
What does density mean?
Density is the number of things—which could be people, animals, plants, or objects—in a certain area. To calculate density, you divide the number of objects by the measurement of the area. The population density of a country is the number of people in that country divided by the area in square kilometers or miles.
How do we calculate density?
density, the mass of a unit volume of a material substance. The formula for density is d = M/V, where d is density, M is mass, and V is volume.
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...............................................................help
Answer:
The maximum height that a cannonball fired at 420 m/s at a 53.0° angles is 5740.48m.
hmax = 5740.48 m
Explanation:
This is an example of parabolic launch. A cannonball is fired on flat ground at 420 m/s at a 53.0° angle and we have to calculate the maximum height that it reach.
V₀ = 420m/s and θ₀ = 53.0°
So, when the cannonball is fired it has horizontal and vertical components:
V₀ₓ = V₀ cos θ₀ = (420m/s)(cos 53°) = 252.76 m/s
V₀y = V₀ cos θ₀ = (420m/s)(cos 53°) = 335.43m/s
When the cannoball reach the maximum height the vertical velocity component is zero, that happens in a tₐ time:
Vy = V₀y - g tₐ = 0
tₐ = V₀y/g
tₐ = (335.43m/s)/(9.8m/s²) = 34.23s
Then, the maximum height is reached in the instant tₐ = 34.23s:
h = V₀y tₐ - 1/2g tₐ²
hmax = (335.43m/s)(34.23s)-1/2(9.8m/s²)(34.23s)²
hmax = 11481.77m - 5741.29m
hmax = 5740.48m
I NEED HELP PLEASE, THANKS!
Identify each of the following as a conductors or insulators. Explain.
-cloth
-dry wood
-tap water
-glass
Answer:
Cloth:
It is an insulator since it can't let electricity pass through
Dry Wood:
It is an insulator and can't conduct electricity.
Tap Water:
It is a good conductor as it contains dissolved salts.
Glass:
It is an insulator since it can't let electricity pass through.
A boy of mass 45kg sits 109cm to the left of the seesaw. Another boy of mass 29000g wants to balance the seesaw. At what distance he needs to sit?
Answer:
166 cm
Explanation:
Given :
d1 =109cm
M1= 45kg
M2=29000g = 29 kg
As we know that Newton second law
[tex]Force\ =\ Mass\ *\ Acceleration[/tex]
Here M1= 45kg
and acceleration=[tex]9.81 m/s^{2}[/tex]
Therefore
[tex]F1=45 * 9.81[/tex]
[tex]F1= 441.45 N[/tex]
M2=29000g = 29 kg
Similarly
[tex]F2= 29 * 9.81\\ F2= 284.4 N[/tex]
Now we using the Principal of moments
[tex]F1 * d1 =F2 *d2[/tex]
[tex]441.5 * 109\ =\ 290\ *\ d2\\48,123.5=290 d2\\d2 =165.9[/tex]
~ d2=166 cm
a material that is not a mixture; it has the same properties all the way through is called. Its 9 letters long and the second letter is u and the eighth letter is c. Its a crossword clue by the way
Answer: The material that is not a mixture; it has the same properties all the way through is called a substance.
Explanation:
A pure substance is a form of matter that has a constant composition and properties that are constant throughout the sample. Hence, it cannot be separated by physical means. Example: Gold
Mixture is a substance which has two or more components which do not combine chemically and do not have any fixed ratio in which they are present. They can be separated by physical means as well. Example: Air
Thus the material that is not a mixture; it has the same properties all the way through is called a substance.
14. A bullet of mass 10 g travelling horizontally with a velocity of
150 m s-l strikes a stationary wooden block and comes to rest
in 0.03 s. Calculate the distance of penetration of the bullet
into the block. Also calculate the magnitude of the force exerted
by the wooden block on the bullet.
Answer:
2.25 m
50 N
Explanation:
Given :
[tex]m=10 g=0.01 kg[/tex]
Initial velocity =U= [tex]150 \ ms^{-1}[/tex]
[tex]Time=t=0.03\ s[/tex]
Final velocity =v=0
We know that
[tex]V=U + at[/tex]
[tex]a\ =\ \frac{V-U}{t}[/tex]
Putting the value of V,U and t in the previous equation we get
[tex]a=\frac{0-150}{0.03} \ \\a=-5000 ms^{-2}[/tex]
According the second law of motion
[tex]s=Ut+\frac{1}{2} *\ at^{2}[/tex]
Putting the value of U,t and a we get
[tex]s=150\ *\ 0.03\ +\frac{1}{2} \ *(-5000)\ * 0.03\ *0.03\\s=2.25\ m[/tex]
We know that
[tex]F=mass * acceleration\ \\F=0.01 * 5000\ \\F=50 N[/tex]
Distance of penetration is 2.25 mThe magnitude of the force Is :50 N
if a room is closed for 2-4 hours then when we open the door we need a little bit of more energy than the actual energy and feel someone is pushing the door from the back side . what is the reason behind it ? which force is that?
Answer:
The reason is because the pressure of the air inside the room drops with time which makes opening the door to require an increased amount of force to make up for the reduced pressure inside the room
Explanation:
From the kinetic theory of gases we have the following relation;
[tex]v_{rms} = \sqrt{\dfrac{3 \cdot K \cdot T}{m} }[/tex]
[tex]p = \dfrac{n \cdot MW \cdot v^2_{rms} }{3 \cdot V}[/tex]
Where:
K = Boltzmann constant
T = Temperature
m = Mass
MW = Molecular weight
V = Volume
[tex]v_{rms}[/tex] = Root mean square velocity
Whereby the room door is closed, the kinetic energy of the air particles will be used up such that the average velocity of the particles will decrease, given that the volume of the room is constant, the pressure inside the room will drop below the original pressure outside the room such that the force on the door due to the outside pressure is larger than the force on the door from inside the room requiring a larger amount of force to overcome the resistance of the now higher outside pressure force.
Henri draws a wave that has a 4 cm distance between the midpoint and the trough. Geri draws a wave that has an 8 cm vertical distance from the bottom of the trough to the top of the crest. Which statement best describes the energy in Henri and Geri’s waves? Henri’s wave has a higher amplitude and more energy. Henri’s wave and Geri’s wave have the same amplitude and the same energy. Henri’s wave and Geri’s wave have the same amplitude, but Geri’s has more energy. Geri’s wave has a higher amplitude and more energy.
Answer:
Henri’s wave and Geri’s wave have the same amplitude and the same energy
Explanation:
The amplitude of a wave is the distance between the midpoint and the trough (or the crest). This is equivalent to half the distance between the trough and the crest. Therefore:
amplitude of Henri's wave: 4 cmamplitude of Geri's wave: 8/2 = 4 cmThe energy of a wave is directly proportional to its amplitude.
Answer:
its letter b
Explanation:
Which condition must be met in order for an equation to be balanced?
Answer:
There must be an equal amount of each element on both sides of the equation. Hope this helps and please marks as the brainliest.
Explanation:
Answer:
The answer is D
Explanation:
Hope this helps!
(d) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate. The type of radiation emitted from a radioactive source can be identified by comparing the properties of the radiation to the properties of alpha, beta and gamma radiation. Describe the properties of alpha, beta and gamma radiation in terms of their: • penetration through materials • range in air • deflection in a magnetic field.
Answer:
Hey!
I did this question and have the answers/potential things you can write!
XD
Explanation:
Here!
structure
•alpha particle consists of a helium nucleus
•alpha particle consists of 2 protons and 2 neutrons
•a beta particle is an electron
•a beta particle comes from the nucleus
penetration
•alpha particles are very poorly penetrating
•alpha particles can penetrate a few cm in air
•alpha particles are absorbed by skin
•alpha particles are absorbed by thin paper
•beta particles can penetrate several metres of air
•beta particles can pass through thin metal plate / foil
•beta particles can travel further than alpha particles in air
•beta particles can travel further than alpha particles in materials eg metals
deflection
•alpha particles and beta particles are deflected in opposite directions in an electric field
•beta particles are deflected more than alpha particles
•alpha particles have a greater charge than beta particles but beta particles have much less mass or beta particles have a greater specific charge than alpha particles
Hope this helps!
Sorry if it's a bit too long!
Which statement is true about the loudness of sound?
A. It is directly proportional to the distance of the listeners from the source.
B. It is inversely proportional to the square of the distance of the listener from the source.
C. It is directly proportional to the square of the distance between the listener from the source.
D. It is inversely proportional to the distance between the listener from the source.
The loudness of sound is inversely proportional to the square of the distance of the listener from the source. (B)
Answer:
B. It is inversely proportional to the square of the distance of the listener from the source.
Explanation:
To which category does galaxy #1 belong? Why does it belong in this category?
Answer:
This galaxy belongs to the elliptical galaxy category. This is because it does not have spiral arms.
Most of the elements in the periodic table are___
Answer:
The most of the elements in the periodic table are metals. The elements cannot be gases and liquids (Molecules are mainly gases and liquids). Metalloids are few. Examples (Germanium, Arsenic)
Help needed Can a body be accelerating if it is moving in circle
Answer:
When a body is moving on a circle it is accelerating because centripetal acceleration is always acting on it towards the center.
Please see the attached picture...
From the above diagram,we can say the acceleration is always acting on the body when it moves in a circle.
Hope this helps.......
Good luck on your assignment.......
Answer:
an object moving in uniform circular motion is moving in a circle with a uniform or constant speed. The velocity vector is constant in magnitude but changing in direction. Because the speed is constant for such a motion, many students have the misconception that there is no acceleration. "After all," they might say, "if I were driving a car in a circle at a constant speed of 20 mi/hr, then the speed is neither decreasing nor increasing; therefore there must not be an acceleration." At the center of this common student misconception is the wrong belief that acceleration has to do with speed and not with velocity. But the fact is that an accelerating object is an object that is changing its velocity. And since velocity is a vector that has both magnitude and direction, a change in either the magnitude or the direction constitutes a change in the velocity. For this reason, it can be safely concluded that an object moving in a circle at constant speed is indeed accelerating. It is accelerating because the direction of the velocity vector is changing.
Explanation: hopes it help u
In which direction will the box move?
3N
15 N
12 N
5 N
A.
to the right
B.
to the left
C.
downward and to the left
upward and to the right
sara walks part way around a swimming pool. she walks 50 yards north, then 20 yards east, then 50 yards south. the magnitude of her displacement during this walk is ______ yards
Answer:
+20 yards
Explanation:
Given:
North = 50 yards
East = 20 yards
South = 50 yards
Required
Calculate the magnitude of displacement
Displacement is a vector quantity and it is a measure of distance taken and the direction of the distance.
Take up directions as positive and down directions as negative.
Similarly, we'll take right direction as positive and left direction as negative.
We understand that;
North is upwards; so, the displacement is +50 yards
East is rightwards; so, the displacement is +20 yards
South is downwards; so the displacement is -50 yards
Hence, her total displacement is
Displacement = +50 yards + 20 yards - 50 yards
Displacement = +20 yards
Hence, Sara's displacement is +20 yards
Conductors and Insulators
Answer:
ConductorsThe substances which allow an electric current to pass through it is called conductors.
Example: Metals like copper,iron ,graphite etc.
InsulatorsThe substances which do not allow the electric current to pass through is called Insulators.
Example: Glass, dry wood ,plastic etc.
Hope this helps...
Good luck on your assignment...