Answer:
If there isn't this type of mechanism, the whole setup will blow even if only one lamp burns out. Doing this mechanism is to decrease the overall resistance resulting in an increased current (Since resistance and current are inversely related) which is the best to blast the fuse.
. A sample of 4 g of cobalt isotope is produced. If the half-life of is 30 years, what will be the mass of the cobalt remaining after 90 years?
Answer:
Half Life = 90/30 = 3 Half lives
Half Life = 30 years
So,
4 g Cobalt after 30 years = 4/2
=> 2 g
2 g Cobalt after next 30 years = 2/2
=> 1 g
1 g Cobalt after next 30 years = 1/2
=> 0.5 g
So, After 90 years, 0.5g of cobalt isotope will be left.
Electrons flowing towards south are deflected towards east by a magnetic
field. What is the direction of magnetic field?
Answer:
The magnetic field is upwards.
Explanation:
You have to use "Right-hand rule", but for electrons, the direction of the magnetic force should be reversed.
This equation is missing which motion variable?
Answer:
Option A. a
Explanation:
Motion variables include:
1. Final velocity (vf).
2. Initial velocity (vi).
3. Time (t).
4. Acceleration (a)
5. Distance (x)
Considering the equation given in the question:
Δx = ½(vf + vi) t
We can see that the acceleration (a) is missing in the equation.
a force is a pull or a push true or false?
Answer:
True
Explanation:
hellllp me please anyone help Light travels from a region of air into a region of air, making an angle of incidence of 60 degrees. Which of the following best describes the path of the light as it moves into the air? A) The light will bend toward the normal B) The light will bend away from the normal C)The light will continue without bending D)The light will move in some manner not determined by the information here.
Answer:
(B)
Explanation:
Because what ever angle the surface is, the light will reflect of of it perpendicular.
A car of mass 800 kg is moving at a uniform velocity of 72 km/hr. Find its
momentum.
[Ans: 16000 kgm/s)
A body of mass 5 kg has momentum of 125 kg m/s. Find the velocity of the body
in motion.
[Ans: 25 mls)
Answer:
hope its helpful to uh...
the temperature of 550g of water is changed from 20.8°C to 25.3°C. How much heat did this sample absorb?
Answer: 10,370.25J
Explanation:
Given the following :
Mass of water = 550g
T1 = 20.8°C
T2 = 25.3°C
Temperature change = (T2 - T1) = (25.3 - 20.8)°C = 4.5°C
Specific heat capacity of water = 4.19Jg^-1C^-1
Recall:
Q = mc∆T
Where ∆T = temperature change, Q = quantity of heat c = specific heat capacity of water, m = mass of water in gram
Q = 550 × 4.19 × 4.5
Q = 10,370.25J
long nonconducting cylinder (radius = 12 cm) has a charge of uniform density (5.0 nC/m3) distributed throughout its volume. Determine the magnitude of the electric field 15 cm from the axis of the cylinder.
Answer:
the magnitude of the electric field = 27.1058 V/m
≈ 27 V/m
Explanation:
given
R(radius enclosed) = 12 cm = 0.12 m
ρ(charge density) = 5.0 nC/m³ = 5.0 × 10⁻⁹C/m³
r(radius from the axis) = 15 cm = 0.15 m
using Gauss law, which states that the electric flux through any closed surface is directly proportional to the total electric charge enclosed by this surface.
attached is the calculation of the question, using Gauss law of electrostatics
Which term describes the amount of energy that is used in a circuit each
second?
O A. Voltage
O B. Power
O c. Current
O D. Resistance
Answer:
The correct answer is power
6) A plane taking off leaves the runway at 329 to the horizontal, travelling at
180kmh 1. How long will it take to climb to an altitude of 1000m?
Answer:
2.7secsExplanation:
The question is not properly written. Here is the correct question
A plane taking off leaves the runway at 32° to the horizontal, travelling at
180km/h. How long will it take to climb to an altitude of 1000m?
This motion of the plane is a projectile motion. From the question, we are to calculate the time taken by the plane to reach the maximum height.
Using the formula tmax = Usin[tex]\theta[/tex]/g
[tex]\theta[/tex] is the angle of projection = 32°
U is the velocity of the plane (in m/s) = 180* 1000/3600 = 50m/s
g is the acceleration due to gravity = 9.8m/s²
tmax = 50sin32°/9.8
tmax = 26.496/9.8
tmax = 2.7sec
2. Find the time taken by the bus to reach the stop. need only group B, 2 answer
Answer:
t = 2 seconds
Explanation:
In 2nd question, the question is given the attached figure.
Initial speed of the bus, u = 0
Acceleration of the bus, a = 8 m/s²
Final speed, v = 16 m/s
We need to find the time taken by the car to reach the stop. Acceleration of an object is given by :
[tex]a=\dfrac{v-u}{t}[/tex]
t is time taken
[tex]t=\dfrac{v-u}{a}\\\\t=\dfrac{16-0}{8}\\\\t=2\ s[/tex]
The bus will take 2 seconds to reach the stop.
the most common mineral group is broken into the subgroups of ferromagnesium and nonferromagnesium
Answer:
They're made of silicon and oxygen.
Explanation:
Electrons that are free to move in metals
Answer:
Brainliest please
Explanation:
I will start by saying that Metals by their very nature are conductors of electricity. Now metals exhibit “metallic bonding” which holds its structure together. Unlike other materials which exhibit covalent bonding, it's atoms are not bonded by “electron sharing”. Rather they are bonded by the availability of valence electrons. Now within a metals atomic structure, the metal atoms lose the electrons in thier outermost shell (valence electrons), thus becoming positively charged ions (cations )
as a motorcycle takes a sharp turn the type of motion that occurs is called ——— motion
Answer:
circular motion
Explanation:
hope this helps you :)
Answer:
Centripetal motion
Explanation:
As a motorcycle takes a sharp turn the type of motion that occurs is called centripetal motion
Use Newton's laws to explain why a falling object dropped from a 57m tower accelerates initially but then reaches constant velocity. Discuss the forces acting on the object
Answer:
At the point of dropping the object, by Newton's first law due to gravitational force [tex]F_g[/tex] = m × g, accelerates
By Newton's Second law the object reaches impacts on the air with the gravitational force resulting in changing momentum of m×(Final Velocity - Initial Velocity)
As the velocity increases, the rate of change of momentum becomes equivalent to the gravitational force and by Newton's third law, the action action and reaction are equal and opposite hence they cancel each other out
The body then moves at a constant uniform motion down according to Newton's first law
Explanation:
At the point the object of mass, m, is dropped from the height of the tower, the only force acting on the object is the gravitational force such that the object has an acceleration which is the acceleration due to gravity, g, and the gravitational force is therefore = m × g
As the speed of the object increases while the object is falling with the gravitational acceleration the rate at which the object cuts through layers of air which (by Newton's first law of motion, are at rest ) has some buoyancy effect also increases therefore, the object is constantly increasingly changing the momentum of the air which by Newton's second law results, at an high enough velocity, and by Newton's third law, in a force equal to the applied gravitational force
Therefore, the force of the air drag becomes equal to the gravitational force, cancelling each other out and the object then moves according to Newton;s first law, in uniform motion of a constant speed while still falling down.
With an initial velocity of 9.8 m / sg, an object is thrown upwards from the roof of a 100 m high building. Determine maximum height from the ground, time it takes to reach the ground, and the speed with which it reaches the ground.
Answer:
104.9 m
5.63 s
45.3 m/s
Explanation:
Given:
y₀ = 100 m
v₀ = 9.8 m/s
a = -9.8 m/s²
Find: y when v = 0 m/s
v² = v₀² + 2a (y − y₀)
(0 m/s)² = (9.8 m/s)² + 2 (-9.8 m/s²) (y − 100 m)
y = 104.9 m
Find: t when y = 0 m
y = y₀ + v₀ t + ½ at²
0 m = 100 m + (9.8 m/s) t + ½ (-9.8 m/s²) t²
0 = 100 + 9.8t − 4.9t²
t = [ -9.8 ± √(9.8² − 4(-4.9)(100)) ] / 2(-4.9)
t = (-9.8 ± 45.3) / -9.8
t = 5.63 s
Find: v when y = 0 m
v² = v₀² + 2a (y − y₀)
v² = (9.8 m/s)² + 2 (-9.8 m/s²) (0 m − 100 m)
v = -45.3 m/s
|v| = 45.3 m/s
A boy is twirling a model airplane on a string 4 feet long. if he twirls the plane at 0.25 revolutions per minute, how far does the plane travel in 4 minutes? round to the nearest tenth.
Answer:
25.13 ft
Explanation:
r = 4 feet
ω=0.25 revolution per minute
=1 revolution in 4 minutes
total number of revolution N = 1 (in 4 minutes )
v=rω
distance traveled = 2×N×π×r
=2×1×π×4
=8π
= 25.13ft in 4mins
I NEED HELP!! PLEASE HELP ME
Answer:
but I can tomorrow if you have time can you come to the meeting tonight but yyyy the person who is this and what
Explanation:
gyyyyyyyyyyyyyyyyy the number of the person who is this and what is the
describe briefly one problem caused by the expansion of metals.
Answer:
The expansion and contraction of materials can also cause problems. For example, bridges expand in the summer heat and need special joints to stop them bending out of shape.A bimetallic strip has two metal strips glued together. One of these metals expands more for each degree temperature rise than that other.
Which of the following is an example of newton second law of motion?
Answer: Its answer C: A wheelbarrow is more difficult to move as More objects are placed inside.
Explanation: The greater the mass of the object the more force is needed to make it move.
Hope this helps!! :)
What is electrical power in terms of current and potential difference? Explain.
Answer:
Ohm's Law:
[tex]V = IR[/tex]
Where V is voltage, I is current and R is resistance
While,
[tex]P = IV[/tex]
Where P is power, I is current and V is voltage (or potential difference)
So, Electrical power is the product of current and potential difference.
*SS2 E_CAT 2020*
*DATE:* FRIDAY, 3RD JULY 2020
*Time allowed:* 40 minutes
*Instruction*: Attempt all questions. Send screenshots of solutions to my number *privately*.
*Take:* specific heat capacity of water = 4200 J/kgK
1. The lower and upper fixed points of a mercury-in-glass thermometer are marked X and 180mm respectively. On a particular day, the mercury meniscus in the thermometer rises to 60mm. If the corresponding reading on a Celsius scale is 20°C, what is the value of X?
2. A resistance thermometer has a resistance of 20 ohm at 0°C and 85 ohm at 100°C. If its resistance is 52 ohm in a medium, calculate the corresponding temperature.
3. A tap supplies water at 26°C while another supplies water at 82°C. If a man wishes to bath with water at 40°C, what is the ratio of the mass of hot water to that of cold water.
4. A metal of mass 1.55kg was heated from 300K to 320K in 6 minutes by a boiling ring of 85 W rating, calculate the specific heat capacity of the metal. {Neglect heat losses to the surrounding.}
5. (i) What is meant by the statement, _the specific heat capacity of copper is 400 J/KgK? (ii) Distinguish between specific heat capacity and thermal capacity deriving the mathematical relationship between.
thank you
Explanation:
2. Heat gained by tap1 = mass1 × SHC × change in temperature
= mass1 × 4200 × (40 - 26)
= mass1 × 58800
Heat lost by tap 2 = mass2 × SHC × change in temperature
= mass2 × 4200 × (82 - 40)
= mass2 × 176400
Heat gained = heat lost
mass1 × 58800 = mass2 × 176400
Ratio of mass 1 to mass 2 = 58800mass1 : 176400mass2
= 1 : 3
Why do force and weight have same units?
Answer:
Weight is a force
Explanation:
Weight is the force of gravity on a mass. It can also be seen through this equation: F=ma, where m is the mass of the object and a is the acceleration of gravity.
A football is kicked at ground level with a speed of 18.6 m/s at an angle of 44.9 to the horizontal.
How much later does it hit the ground ?
Answer:
t = 3.79 s
Explanation:
We have,
A football is kicked at ground level with a speed of 18.6 m/s at an angle of 44.9 to the horizontal.
It means that,
Initial speed of a football, u = 18.6 m/s
Final speed of a football, v = 0 (when it hits the ground)
It would under the action of gravity. Let t is the time of motion. So, using equation of kinematics to find it.
v=u+at
a=-g
[tex]t=\dfrac{v-u}{a}\\\\t=\dfrac{0-18.6}{-9.8}\\\\t=1.89\ s[/tex]
The total time before the ball hits the ground is the sum of time taken to come down and time taken to go up. So, total time is 2×1.89 = 3.79 s
A particle starts at velocity of 3 m/s and accelerates uniformly at 1.5m/s². How far does it go in 1s, 5s and the 4th second
Answer:
Please go through the 2nd photo for the last part of the question that is " how far does it go in the 4th second "
Answer:
[tex]x=\frac{1}{2}at^{2}+v_{0}t\\\\1s: x=0.75(1)^{2}+3(1)=3.75m\\5s: x=0.75(5)^{2}+3(5)=33.75m\\4th=3s>>4s: x_{4} =(0.75(4)^{2}+3(4))-(0.75(3)^{2}+3(3))=8.25m[/tex]
I've written all the needed equations for you. All you have to do is some replacements.
Please do not hesitate to ask further questions.
PLEASE I NEED HELP WITH THIS ASAP
A student finds a rock on the way to school. In the laboratory he determines that the volume of the rock by placing the rock in a graduated cylinder with 50 cm3 of water and watched the water rise to 72.7 cm3. The student determined the mass is 39.943 g through the use of a triple beam balance. What is the density of the rock?
With step by step explanation
Answer:
density=mass/volume
39.943/22.7=1.75
Explanation:
An object in a certain direction with an acceleration in the perpendicular direction
Answer:
An object moving in certain direction with an acceleration in the perpendicular direction. The above condition is possible . Example of such situation in life would be when stone tied to a string whirling in a circular path
Hope this helps and pls mark as BRAINLIEST :)
Please help. Basic. Brainliest will be given.
Answer:
28.7 m at 46.9°
Explanation:
The x component of the displacement is:
x = 6 m cos 0° + 25 m cos 57°
x = 19.6 m
The y component of the displacement is:
y = 6 m sin 0° + 25 m sin 57°
y = 21.0 m
The total displacement is found with Pythagorean theorem:
d = √(x² + y²)
d = 28.7 m
And the direction is found with trig:
θ = tan⁻¹(y/x)
θ = 46.9°
Answer:
Distance of displacement = 28.71 m
Angle of displacement = 46.91 degrees
Explanation:
convert all individual displacements to simple vectors.
6m east -> <6,0>
25m at 57 -> <25cos57, 25sin57>
Total displacement = sum of two vectors
= <6+25cos57, 0+25sin57>
=<19.62, 20.97>
Magnitude of displacement
= sqrt(19.62^2+20.97^2)
= 28.71
Direction of displacement
= atan2(20.97,19.62)
= 46.91 degrees
Select the correct the answer.
What do the circled arrows in the image indicate?
A. CO2 absorbed by the atmosphere
B. CO2 released to the atmosphere
C. oxygen absorbed by the atmosphere
D. oxygen released by the atmosphere
Answer:
it shows that co2 is absorbed by the atmosphere.
when the animals respire they produce co2 which is release in atmosphere and in presence of sunlight and chlorophyll the plants manufacturs the food and releases the oxygen in the atmosphere .
hope it helps..
Answer:
Its A
Explanation:
A vehicle traveling on wet or slick roads can begin to _________ as water forms a barrier between the road and the tires and traction is lost as the wheels start to ride on top of the water and not the road surface. a) skid b) hydroplane c) lose traction d) splash water on to the engine
Answer: B.) HYDROPLANE
Explanation: The term hydroplane can be used to refer to a condition which usually occur during a downpour or on surfaces covered by water. It occurs when water forms a barrier or comes in between the frictional grip which occurs between the road surface and the car tyres. The contact between the car tyres and the road surface is supposed to give adequate frictional support which prevents the car from skidding or skidding uncontrollably on the road surface. However, when water comes invetween the surface, traction is lost and skidding results due to very low Coefficient of friction between the road and Tyre which was supposed to provide a firm grip between the tyres and the road surface.
When a vehicle is traveling on wet or slick roads, hydroplaning can occur. The correct answer is b) hydroplane.
When a vehicle is traveling on wet or slick roads, hydroplaning can occur. Hydroplaning happens when a layer of water builds up between the tires of the vehicle and the road surface, leading to a loss of traction.
This loss of traction can cause the vehicle to skid or slide, making it difficult to control. The tires ride on top of the water rather than maintaining contact with the road, resulting in reduced traction and control of the vehicle.
Therefore, When a vehicle is traveling on wet or slick roads, hydroplaning can occur. The correct answer is b) hydroplane.
To know more about hydroplaning:
https://brainly.com/question/33723980
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