A block of mass 4 kg rests on a horizontal surface without friction, when subjected to the action of 5 horizontal forces as shown in the figure (wait for the figure). Answer: (a) How strong is the resulting force? (b) What is the direction of the resulting force? (c) If the block takes action to come out of inertia, what will be its acceleration acquired?

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)

Answer:

  (vix, viy) = (14.7 m/s, 10.3 m/s)

Explanation:

The velocities of interest are ...

  (vix, viy) = (vi)(cos(35°), sin(35°)) = (18 m/s)(cos(35°), sin(35°))

  (vix, viy) = (14.7 m/s, 10.3 m/s)

Answer:

First one = 14.7

Second one = 10.3

Explanation:

EDGE

Answer:

a 1.26 km b 10.5 m/s

Explanation:

A. Distance travelled by the schooterist

Since the schooterist travels in a circular path, the distance moved is the circumference of a circle, C with radius r = 0.2 km

C = 2πr

= 2π(0.2 km)

= 1.26 km

So, the distance travelled by the schooterist is 1.26 km

B. The velocity of the schooterist

The velocity of the schooterist v = distance travelled/time

distance travelled = 1.26 km = 1260 m

time = 2 minutes = 2 × 60 s = 120 s

So, V = 1260 m/120 s

= 10.5 m/s

So, the velocity of the schooterist is 10.5 m/s

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

Answer:

The answer is below

Explanation:

There are various reasons for a power station not to work at maximum output all the time. These includes technical constraints, such as

1.  Availability of the plant: sometimes the availability of generating plants may affect capacity factor, which may be caused due to plant part break down, or routine servicing.

2.   Economic reasons: the capacity factor of a generating plant can be affected due to the level of usage at peak performance, as the cost of running the plant at peak form may be expensive to maintain.

3.  Availability of the energy resource: this often applicable to generating plants using renewable energy, this is because, energy source such as wind, solar and water may not be readily available all the year round as they can be seasonal. Also, the maximum output can be affected even if the generating plant is using non renewable energy, as there maybe some times, unavailability or low supply of the crude oil or fossil fuel.

Also, the main reason in which the capacity factor for non-renewables is always higher than for renewables, is because of the availability factor, or availability of the energy resources. This is because renewable energy such as water, wind, and solar are not readily available all the time, and are subject to atmospheric conditions, unlike non renewable energy such as crude oil, which can be readily available by purchasing them.

Answer:

(a) 3.22 m

(b) The vertical velocity, [tex]v_y[/tex], at maximum height is 0 m/s, the horizontal velocity, vₓ, is 12.72 m/s

(c) The acceleration at maximum height = g = 9.81 m/s²

(d) The time it takes for the paper to reach the balcony is 1.212 seconds

(e) The horizontal range, of the paper is 15.42 m.

Explanation:

(a) Given that we re given a projectile motion, we have the following governing equations;

y = y₀ + v₀·sin(θ₀)·t - 0.5×g·t²

[tex]v_y[/tex] = v₀·sin(θ₀) - g·t

Where:

y = Height of the paper

y₀ = Initial height of the paper = Ground level = 0

v₀ = Inititial velocity of the paper = 15.0 m/s

θ₀ = Angle in which the paper is thrown = 32° above the horizontal

g = Acceleration due to gravity = 9.81 m/s²

t = Time taken to reach the height h

[tex]v_y[/tex] = Vertical velocity of the paper

At maximum height, [tex]v_y[/tex] = 0, therefore;

[tex]v_y[/tex] = v₀·sin(θ₀)·t - g·t = 0

v₀·sin(θ₀) = g·t

t = v₀·sin(θ₀)/g = 15×sin(32°)/9.81 = 0.81 seconds

y = y₀ + v₀·sin(θ₀)·t - 0.5×g·t² = 0 + 15×sin(32°)×0.81-0.5×9.81×0.81² = 3.22 m

(b) The vertical velocity, [tex]v_y[/tex], at maximum height = 0 m/s, the horizontal velocity, vₓ, = 15×cos(32°) = 12.72 m/s

(c) The acceleration at maximum height = g = 9.81 m/s²

(d) The time it takes to maximum height = 0.81 seconds

The time the paper will take to fall to 1.25 m above the ground, which is 3.22 - 1.25  = 1.97 meters below maximum height is therefore given as follows;

y = y₀ + v₀·sin(θ₀)·t - 0.5×g·t²

Where:

v₀ = 0 m/s at maximum height

y = -1.97 m downward motion

y₀ = 0 starting from maximum height downwards

1.97 = 0 + 0·sin(θ₀)·t - 0.5×9.81×t²

-1.97 =  - 0.5×9.81×t²

t = (-1.97)/(-0.5*9.81) = 0.402 seconds

The time the paper will take to fall to 1.25 m above the ground = 0.81+0.402 = 1.212 seconds

Therefore, the time it takes for the paper to reach the balcony = 1.212 seconds

(e) The horizontal range, x, is given by the relation;

x = x₀ + v₀·cos(θ₀)·[tex]t_{tot}[/tex]

x₀ = Starting point of throwing the paper = 0

[tex]t_{tot}[/tex] = Total time of flight of the paper

∴ x = x₀ + v₀·cos(θ₀)·[tex]t_{tot}[/tex] = 0 + 15×cos(32°)×1.212 = 15.42 m

The horizontal range, of the paper = 15.42 m.

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!

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:

The energy of a wave is directly proportional to its amplitude.

Answer:

its letter b

Explanation:

Those quantities which can be measured directly or indirectly is called physical quantities.

There are two types of physical quantities.They are:

Those quantity which are not dependent upon any quantity are called fundamental quantity.for eg: length,mass time etc.

Those quantity which are dependent upon other quantities are called derived Quantity. for eg: volume,area etc.

Temperature is the degree of hotness and coldness of a body.Temperature is measured in degree,Celsius,degree Fahrenheit or Kelvin scale.Temperature is measured by using thermometer.

Hope this helps....

Good luck on your assignment.....

Answer:

Explanation: Research states that ;

Thermodynamic temperature is the measure ( absolute)  of temperature and is one of the principal parameters of thermodynamics.

It uses the kelvin scale for measurement and selects the triple point of water at 273.16 K as the fundamental fixing point.

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]

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.

Answer:

A - 4.5 m/s

Explanation:

31,500/7,000= 4.5

Answer:

the speed is 3m/s

Explanation:

below is the working

Answer:

The ball is going to be spinning in a clockwise direction.

Answer:

The substances which allow an electric current to pass through it is called conductors.

Example: Metals like copper,iron ,graphite etc.

The 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...

Answer:

This galaxy belongs to the elliptical galaxy category. This is because it does not have spiral arms.

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

Answer: calculate the free fall distance and velocity without air resistance from, the free fall.

Explanation:

To find out something's speed (or velocity) after a certain amount of time, you just multiply the acceleration of gravity by the amount of time since it was let go of. So you get: velocity = -9.81 m/s^2 * time, or V = gt. The negative sign just means that the object is moving downwards

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

Answer:

False

Explanation:

It is located in the little dipper whose stars are more faint.

Answer:

a. All the laboratory equipment given are very basic equipment used in all the laboratories. Name of each equipment is as follows:

b. Use of each laboratory equipment identified is:

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:

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!!!

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.

Answer:

i can not read that sorry

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.

Answer: B

V = 7576 m/s

Explanation: Given that the

circular radius R = 7,000,000 m,

The acceleration due to Earth's gravity is 8.2 m/s2

Let's use gravitational field strength formula to get the mass of the satellite.

g = Gm/R^2

Where G = 6.674×10^−11m3⋅kg−1⋅s−2

Substitutes all the parameters into the formula

8.2 = (6.674×10^-11 × M)/(7000000)^2

Cross multiply

4.018 × 10^14 = 6.674×10^−11M

Make M the subject of formula

M = 4.018 × 10^14 ÷ 6.674×10^−11

M = 6.02 × 10^24 kg

The Force of attraction experienced by the satellite will be

F = mg

F = 6.02 × 10^24 × 8.2

F = 4.94 × 10^25 N

But centripetal force is

F = MV^2/ R

Where V = velocity of the satellite

Substitute F, M and R into the formula

4.94×10^25 = (6.02×10^24V^2)/ 7 ×10^6

Cross multiply

3.46 × 10^32 = 6.02×10^24V^2

Make V^2 the subject of formula

V^2 = 3.46×10^32 ÷ 6.02×10^24

V^2 = 57403600.2

Find the square root of the value to get V

V = 7576 m/s

The required velocity of the satellite is 7576 m/s approximately

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]

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