Mass and velocity are the two terms which affect momentum of a bicycle going hill down.
Explanation:
As we know that Momentum describes the motion of an object. It is the combination of the objects mass and velocity.
So, obviously with no doubt mass and velocity are the two terms which affect momentum.
Momentum(p) = Mass(m) * Velocity(v)
The momentum also depends upon the mass and speed of the object.
More the mass of the object more is the momentum.
Depending upon the gravity and bicycle's motion speed momentum varies.
Bicycle moves faster the down hill if it moves with some speed as it has lesser mass the momentum also will be less.
Answer:

Explanation:
Mass and weight ain't the same thing. So, for calculating weight we would use Newton's 2nd Law of Motion i.e. Force = Mass × Acceleration.
According to question,
The mass is 20kg
Acceleration is 9.8 m/s^2
Putting the given values into the formula,
F = 20 × 9.8
F = 196N
So, the weight of the rock is 196 N
Hope it helps!<3
Answer:
11.72 mm
Explanation:
The gravitational potential energy equals the potential energy of the spring hence
where m is the mass of object, g is the acceleration due to gravity, h is the height, k is the spring constant and x is the extension of the spring
where \theta is the angle of inclination and d is the sliding distance
Making x the subject then
Substituting the given values then

Answer:
The hill should be not less than 0.625 m high
Explanation:
This problem can be solved by using the principle of conservation of mechanical energy. In the absence of friction, the total mechanical energy is conserved. That means that
is constant, being U the potential energy and K the kinetic energy


When the car is in the top of the hill, its speed is 0, but its height h should be enough to produce the needed speed v down the hill.
The Kinetic energy is then, zero. When the car gets enough speed we assume it is achieved at ground level, so the potential energy runs out to zero but the Kinetic is at max. So the initial potential energy is transformed into kinetic energy.

We can solve for h:

The hill should be not less than 0.625 m high