I would say friction because it requires to surfaces in order for the force to take place
correct me if I'm wrong.
The answer would be 72 miles. Hope this helped.
Answer:
The amount of work the factory worker must to stop the rolling ramp is 294 joules
Explanation:
The object rolling down the frictionless ramp has the following parameters;
The mass of the object = 10 kg
The height from which the object is rolled = 3 meters
The work done by the factory worker to stop the rolling ramp = The initial potential energy, P.E., of the ramp
Where;
The potential energy P.E. = m × g × h
m = The mass of the ramp = 10 kg
g = The acceleration due to gravity = 9.8 m/s²
h = The height from which the object rolls down = 3 m
Therefore, we have;
P.E. = 10 kg × 9.8 m/s² × 3 m = 294 Joules
The work done by the factory worker to stop the rolling ramp = P.E. = 294 joules
Not totally sure but i would say a normal? its not refraction or incidence if its perpendicular and i dont think its a mirror if its an imaginary line so yeah normal (normals are always perpendicular to their surface too i think so)
The new speed of car is 10.9 m/s
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According to the principle of momentum conservation, momentum is only modified by the action of forces as they are outlined by Newton's equations of motion; momentum is never created nor destroyed inside a problem domain.
Mass of the railroad car, m₁ = 7950 kg
Mass of the load, m₂ = 2950 kg
It can be assumed as the speed of the car, u₁ = 15 m/s
Initially, it is at rest, u₂ = 0
Let v is the speed of the car. It can be calculated using the conservation of momentum as :




Therefore, the new speed of care is 10.9 m/s
Learn more about momentum here:
brainly.com/question/22257327
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