Answer:
Explanation:
Given:
- width of door,
- height of the door,
- thickness of the door,
- mass of the door,
- torque on the door,
<em>∵Since the thickness of the door is very less as compared to its other dimensions, therefore we treat it as a rectangular sheet.</em>
- For a rectangular sheet we have the mass moment of inertia inertia as:
We have a relation between mass moment of inertia, torque and angular acceleration as:
Answer:
We can conclude that there is a decrease in kinetic energy of the particles due to their elastic collision, since kinetic energy is directly proportional to squared velocity of the particles.
Explanation:
Given:
initial velocity of particle A, Ua = 5m/s
initial velocity of particle B, Ub = 10 m/s
final velocity of particle A, Va = 4m/s
final velocity of particle B, Vb = 7m/s
For particle A:
The final velocity is 1 less than the initial velocity.
For particle B:
The final velocity is 3 less than the initial velocity.
We can conclude that there is a loss in kinetic energy due to elastic collision of the two particles, since kinetic energy is directly proportional to squared velocity of the particles. A decrease in velocity means decrease in kinetic energy.
Answer:
Part a) When collision is perfectly inelastic
Part b) When collision is perfectly elastic
Explanation:
Part a)
As we know that collision is perfectly inelastic
so here we will have
so we have
now we know that in order to complete the circle we will have
now we have
Part b)
Now we know that collision is perfectly elastic
so we will have
now we have
<h3><u>Answer</u>;</h3>
= 22°
<h3><u>Explanation</u>;</h3>
- According to Snell's law, the ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant. The constant value is called the refractive index of the second medium with respect to the first.
- Therefore; Sin i/Sin r = η
In this case; Angle of incidence = 90° -60° =30°, angle of refraction =? and η = 1.33
Thus;
Sin 30 / Sin r = 1.33
Sin r = Sin 30°/1.33
= 0.3759
r = Sin^-1 0.3759
= 22.08
<u>≈ 22°</u>
The kinetic energy of the small ball before the collision is
KE = (1/2) (mass) (speed)²
= (1/2) (2 kg) (1.5 m/s)
= (1 kg) (2.25 m²/s²)
= 2.25 joules.
Now is a good time to review the Law of Conservation of Energy:
Energy is never created or destroyed.
If it seems that some energy disappeared,
it actually had to go somewhere.
And if it seems like some energy magically appeared,
it actually had to come from somewhere.
The small ball has 2.25 joules of kinetic energy before the collision.
If the small ball doesn't have a jet engine on it or a hamster inside,
and does not stop briefly to eat spinach, then there won't be any
more kinetic energy than that after the collision. The large ball
and the small ball will just have to share the same 2.25 joules.
