Question

A 1 kg cart traveling at a constant 2 m/s across a level lab table 0.8 m above the floor is stopped in a distance of .2 m. The amount of work required to stop the cart is?

1) 1 J
2) 2 J
3) 2.5 J
4) 4 J

Answer 1

The amount of work required to stop the 1 kg cart traveling at a constant speed of 2 m/s is 2 J.

Step-by-step explanation:

The work done to stop the cart can be calculated using the principle of work and the concept of kinetic energy. The formula for calculating work is:
Work = force × distance

In this case, the force required to stop the cart is the frictional force between the cart and the lab table. The distance over which the force acts is the distance the cart travels before coming to a stop.

To calculate the work, we need to find the frictional force. Since the cart is stopped, the kinetic energy is converted into work. So:
Work = Change in kinetic energy

The kinetic energy of the cart is given by:
Kinetic energy = 0.5 × mass × velocity^2

Using the given values:
Mass = 1 kg
Velocity = 2 m/s

Substituting these values into the formula for kinetic energy:
Kinetic energy = 0.5 × 1 kg × (2 m/s)^2 = 2 J

Therefore, the amount of work required to stop the cart is 2 J (option 2).