The amount of work done by two boys who apply 200 N of force in an unsuccessful attempt to move a stalled car is 0.
Answer: Option B
<u>Explanation:
</u>
Work done is the measure of work done by someone to push an object from its present position. We can also define work done as the amount of forces needed to move an object from its present position to another position. So the amount of work done is directly proportionate to the product of forces acting on the object and the displacement of the object.

So in this present case, as the two boys have done an unsuccessful attempts to push a stalled car so that means the displacement of the car is zero as there is no change in the position of the car. But they have applied a force of 200 N each. So the amount of work done will be

Thus, the amount of work done by two boys will be zero due to their unsuccessful attempt to move a stalled car.
Answer:
B
Explanation:
V=IR I= curren V=volt R=resistor
8=2.R 8/2=R R=4
Oncology is the study of cancer, so the doctors are called oncologists
Answer:
If the frequency of the motion of a simple harmonic oscillator is doubled , then maximum speed of the oscillator changes by the factor 2
Explanation:
We know that in a simple harmonic oscillator the maximum speed is given by
= 
Here A is amplitude which is constant , so from above equation we see that maximum speed is directly proportional to
of the oscillation .
Since 
= 2
Where
is the maximum speed when frequency is doubled .
Answer:
125.83672 seconds
Explanation:
P = Power of the horse = 1 hp = 746 W (as it is not given we have assumed the horse has the power of 1 hp)
m = Mass of professor = 103 kg
g = Acceleration due to gravity = 9.8 m/s²
h = Height of professor = 93 m
Work done would be equal to the potential energy

Power is given by

The time taken by the horse to pull the professor is 125.83672 seconds