Answer:
(a) The speed of the first particle is 1.75 m/s. The speed of the second particle is 6.9 m/s after the collision.
(b) The speed of the first particle is 3.45 m/s in the negative direction. The speed of the second particle is 1.73 m/s.
(c) The final kinetic energy of the incident particle in part (a) and part(b) is 0.0031 J and 0.011 J, respectively.
Explanation:
(a)
In an elastic collision, both momentum and energy is conserved.

Combining these equations will give the speed of the second particle.

We can use this to find the speed of the first particle.

(b)
If m_2 = 10g.


The minus sign indicates that the first particle turns back after the collision.
(c)
The final kinetic energy of the particle in part (a) and part (b) is
Answer:
F = 39.2 N
Explanation:
Since, the object is in uniform motion. Therefore, the frictional force on object will be:
Frictional Force = μk N = μk mg
where,
μk = coefficient of kinetic friction = 0.2
m = mass of crate = 10 kg
g = 9.8 m/s²
Therefore,
Frictional Force = (0.2)(10 kg)(9.8 m/s²)
Frictional Force = 19.6 N
The horizontal component of force must be equal to this frictional force to continue the uniform motion:
F Sin 30° = 19.6 N
F = 19.6 N/Sin 30°
<u>F = 39.2 N</u>
Answer:
I believe the answer to be B.
Explanation:
Without food, the whales would die.