Answer:
48.16 %
Explanation:
coefficient of restitution = 0.72
let the incoming speed be = u
let the outgoing speed be = v
kinetic energy = 0.5 x mass x 
- incoming kinetic energy = 0.5 x m x
- coefficient of restitution =

0.72 =
v = 0.72u
therefore the outgoing kinetic energy = 0.5 x m x 
outgoing kinetic energy = 0.5 x m x 
outgoing kinetic energy = 0.5184 (0.5 x m x
)
recall that 0.5 x m x
is our incoming kinetic energy, therefore
outgoing kinetic energy = 0.5184 x (incoming kinetic energy)
from the above we can see that the outgoing kinetic energy is 51.84 % of the incoming kinetic energy.
The energy lost would be 100 - 51.84 = 48.16 %
Answer: The 5 uses of mechanical energy are: 1) Hammering a nail
2) Using Dart gun 3) Moon 4) Hydropower plant 5) Sharping a pencil.
Answer: 0.076 m/s
Explanation:
Momentum is conserved:
m v = (m + M) V
(0.111 kg) (55 m/s) = (0.111 kg + 80. kg) V
V = 0.076 m/s
After catching the puck, the goalie slides at 0.076 m/s.
Answer: Top left to bottom right, top right to bottom left
Explanation:
A linear position time graph means a horizontal line on the velocity graph so top left matches the bottom right
With the process of elimination, bottom left matches the top right
Answer: a) 2.5 * 10^14, b) t = 1.2*10^-8 s, c) F = 2.2775 * 10^-15 N
Explanation: Since it starts from rest, initial velocity = 0, final velocity (v) = 3*10^6 m/s, distance covered (s) = 1.80cm = 1.80/100 = 0.018m
Since the force on the electron is constant, it acceleration will be constant too thus making newton's laws of motion valid.
Question a)
To get the acceleration, we use the formulae that
v² = u² + 2as
But u = 0
v² = 2as
(3*10^6)² = 2*a*(0.018)
9* 10^12 = 0.036*a
a = 9 * 10^12 / 0.036
a = 250 * 10^12
a = 2.5 * 10^14 m/s².
Question b)
To get the time, we use
v = u + at
But u = 0
v = at
3*10^6 = 2.5 * 10^14 * t
t = 3*10^6 / 2.5*10^14
t = 1.2*10^-8 s
Question c)
To get the force, we use the formulae below
F = ma
F = 9.11*10^-31 * 2.5 * 10^14
F = 22.775 * 10^-17
F = 2.2775 * 10^-15 N