Answer: vacuum
Explanation: The vacuum is the medium from where the sound wave cannot pass. A vacuum is basically an area without any air. Since the sound wave is a mechanical wave that's why it cannot travel through a medium where there is no matter of vibrations to works in, i.e, it can't travel through a vacuum.
This is a problem of conservation of momentum
Momentum before throwing the rock: m*V = 96.0 kg * 0.480 m/s = 46.08 N*s
A) man throws the rock forward
=>
rock:
m1 = 0.310 kg
V1 = 14.5 m/s, in the same direction of the sled with the man
sled and man:
m2 = 96 kg - 0.310 kg = 95.69 kg
v2 = ?
Conservation of momentum:
momentum before throw = momentum after throw
46.08N*s = 0.310kg*14.5m/s + 95.69kg*v2
=> v2 = [46.08 N*s - 0.310*14.5N*s ] / 95.69 kg = 0.434 m/s
B) man throws the rock backward
this changes the sign of the velocity, v2 = -14.5 m/s
46.08N*s = - 0.310kg*14.5m/s + 95.69kg*v2
v2 = [46.08 N*s + 0.310*14.5 N*s] / 95.69 k = 0.529 m/s
Answer:
is a field force, as gravity does not physically apply force and does not require proximity.
Explanation:
We will solve this question using the second law of motion which states that force is directly equal to the product of mass and acceleration.

Where,
- F is force
- m is mass
- a is acceleration
In our case,
- F = ?
- m = 2500 kg
- a = 20m/s

<em>Thus, The force of 50000 Newton is required to accelerate a car of 2500 kg...~</em>
Kinetic energy. thermal energy (a low form of energy ) is a form of kinetic energy as it is produced as a result of motion of particles either if they vibrate at their position or they move along longer paths. Motion produces friction or resistance which leads to excitation and thus the heat is produced. The higher the motion of the particles, the higher would be the thermal energy.