107k views
22 votes
PLEASE HELP ME

Determine whether the objects in the following problems have kinetic energy (KE) or potential energy (PE). Then, use the appropriate formula to calculate the answer.


You serve a volleyball with a mass of 2 kg. The ball leaves your hand with a speed of 30 m/s. The ball has kinetic energy. Calculate it.


A baby carriage is sitting at the top of a hill that is 20 m high. The carriage with the baby in it weighs 10 kg. The carriage has potential energy. Calculate it.


A car is traveling with a velocity of 20 m/s and has a weight (mass) of 1000 kg. The car has kinetic energy. Calculate it.


There is a bell at the top of a tower that is 20 m high. The bell weighs 100 kg. The bell has potential energy. Calculate it.
KE = (0.5)(m)(v)2


Here are the formulas:

m = mass (in kg

v = velocity (in m/s)

PE = mx g x h

m = mass (in kg

On Earth, gravity, g = 9.8 m/s2

h = height (in m)

1 Answer

8 votes

Answer: The energy of the ball is 945 Joule

Explanation: A volleyball with a mass of leaves the hand with a speed of .

To find:

The total energy of the ball.

Consider that the ball exists moving very close to the ground. Hence its potential energy should be zero.

If the ball will possess kinetic energy by the virtue of its motion.

So, net energy or kinetic energy:

Kinetic energy

Therefore, the energy of the ball is 945 Joule.

User PAA
by
4.9k points