Explanation:
Given that,
The mass of rock, m = 2.35-kg
It was released from rest at a height of 21.4 m.
(a) The kinetic energy is given by : 
As the rock was at rest initially, it means, its kinetic energy is equal to 0.
(b) The gravitational potential energy is given by : 
It can be calculated as :

(c) The mechanical energy is equal to the sum of kinetic and potential energy such that,
M = 0 J + 492.84 J
M = 492.84 J
Hence, this is the required solution.
It's B.
The current passing through each bulb is the same. As you add more light bulbs, the current will decrease in each, but it will always be the same current passing through each one.
Explanation:
The kinetic energy is basically the energy possesses by virtue of a body's motion
1. The truck moving to the quarry
let the mass be x
and the velocity is given as 20m/s
we know that the kinetic energy is given as
KE=1/2mv^2
KE=1/2(x)*20^2
KE=1/2(x)400
KE=200x
2. The truck leaving to the quarry
let the mass be 2x
and the velocity is given as 20m/s
we know that the kinetic energy is given as
KE=1/2mv^2
KE=1/2(2x)*20^2
KE=1/2(2x)400
KE=400x
From the analysis the kinetic energy is a function of mass, doubling the mass doubles the kinetic energy
Answer:
B. the astronaut will never catch the first bounce.
Explanation: