Explanation:
6a) Work = force × distance
W = Fd
W = (60 N) (10 m)
W = 600 J
6b) Change in energy = work
ΔKE = 600 J
7a) Kinetic energy is half the mass times the square of the velocity.
KE = ½ mv²
KE = ½ (0.4 kg) (25 m/s)²
KE = 125 J
7b) Work = change in energy. When the ball is stopped, it has zero kinetic energy.
W = ΔKE
W = 0 J − 125 J
W = -125 J
According to the statements the number of electrons is 150, then
e = 150
But there is a positive charge of +22e, then the number of protons would be
p = 150+172
If the mass of the electrons is
And the mass of the protong is
We have that the total mass of the system would be
Answer:
A
Explanation:
When friction slows a sliding block, <u>the kinetic energy of the block is transformed into internal energy
.</u>
<em>The frictional movement of two surfaces over one another leads to the conversion of some of their kinetic energies to another energy - heat or thermal energy. Hence, the temperatures of the objects are raised in the process. </em>
<u>Therefore, when a sliding block is slowed down due to friction, some of the kinetic energy of the block would be transformed into internal energy in the form of heat.</u>
The correct option is A.
Answer:
Explanation:
The velocity of the wrench must be equal to the velocity of the truck . So momentum of the wrench before it hits the wall
= mv = 6 x 13.3 = 79.8 kg m /s
If resisting force of wall be F , impulse on the wrench = F x time
= F x .07
Impulse = change in momentum of the wrench = mv - 0 = mv = 79.8 kgm/s
So F x .07 = 79.8
F = 1140 N .
The actual answer is 7/100
