Answer:
51.2 J, 86.2 J, 137.4 J
Explanation:
The kinetic energy of the ball is given by:
where
m = 0.40 kg is its mass
v = 16 m/s is its speed
Substituting,
The potential energy of the ball is given by
where
m = 0.40 kg
is the acceleration of gravity
h = 22 m is the heigth of the cliff
Substituting,
Finally, the total mechanical energy is the sum of the kinetic energy and the potential energy:
Answer:
h = 22.35 m
Explanation:
given,
initial speed of the rock,u = 0 m/s
length of the window,l = 2.7 m
time taken to cross the window,t = 0.129 s
Speed of the rock when it crosses the window
v = 20.93 m/s
height of the building above the window
using equation of motion
v² = u² + 2 g h
20.93² = 0² + 2 x 9.8 x h
h = 22.35 m
Hence, the height of the building above the top of window is equal to h = 22.35 m
Answer:
The impulse applied by the stick to the hockey park is approximately 7 kilogram-meters per second.
Explanation:
The Impulse Theorem states that the impulse experimented by the hockey park is equal to the vectorial change in its linear momentum, that is:
(1)
Where:
- Impulse, in kilogram-meters per second.
- Mass, in kilograms.
- Initial velocity of the hockey park, in meters per second.
- Final velocity of the hockey park, in meters per second.
If we know that ,
and
, then the impulse applied by the stick to the park is approximately:
The impulse applied by the stick to the hockey park is approximately 7 kilogram-meters per second.