Question

Directions: Consider a 2-kg bowling ball sits on top of a building that is 40 meters tall. It falls to the grou

Answer 1

Answer:

1) Kinetic energy

2) 784 J

3) 392 J

4) 392.04 J

Explanation:

1) Potential energy is energy stored in an object due to its position/ height. Kinetic energy is the energy of an object due to motion.

When the bowling hits the ground, it is almost on zero height. Less height makes its potential energy almost zero. While bowling is in a moving phase, it has covered a 40 meters distance to reach on the ground so it posses more kinetic energy.

2) To measure the potential energy, there is a formula,

P.E = mass x gravity x height

= m x g x h

In given data we have,

mass = 2 kg

height = 40 m

gravity = 9.8 m/s2

put the values in the formula

P.E = 2 x 9.8 x 40

P.E = 784J

3) when bowling on its halfway to fall, it covers its half distance. The bowling is on its 20 m height. At that moment its potential energy will be

P.E = m x g x h

P.E = 2 x 9.8 x 20

P.E = 392 J

4) On the bowling halfway to fall, it is traveling 19.8 meters per second, its kinetic energy will be

kinetic energy = 1/2 x mass x velocity²

K.E = 1/2 x 2 x (19.8)²

K.E = 392.04 J