Answer:
I would say that I agree with the one that said that each hill must be lower than the previous one and use the principle of conservation of energy to explain.
Explanation:
Roller coaster are usually designed such that its total energy remains conserved at any point on the track. Now, the law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be conserved over time. At certain height on the track, the total energy of the roller coaster is in form of potential energy, which gets converted to kinetic energy as soon as it starts sliding down the hill till get to the hill's endpoint where it has maximum kinetic energy. The cycle of sliding from a high point on the track to a low point on the track means there is potential energy is converted to kinetic energy and kinetic energy then converts back to potential energy and the cycle continues.
However, due to the effect of gravity and frictional force between the track and the coaster, the energy of the coaster is gradually reduces, so it becomes a bit difficult for the coaster to move to the next hill of the same height. It is for this reason that each hill must be lower than the previous one, so that the coaster can overcome the next hill's height with its reduced energy until it loses all its energy and comes to a stop.
Answer:
The velocity of the particle from T = 0 s to T = 4 s is;
0.5 m/s
Explanation:
The given parameters from the graph are;
The initial displacement (covered) at time, t₁ = 0 s is x₁ = 1 m
The displacement covered at time, t₂ = 4 s is x₂ = 3 m
The graph of distance to time, from time t = 0 to time t = 4 is a straight line graph, with the velocity given by the rate of change of the displacement to the time which is dx/dt which is also the slope of the graph given as follows;


The velocity of the particle from t = 0 s to t = 4 s = 1/2 m/s = 0.5 m/s.
Answer:

Explanation:
The equivalent of Newton's second law for rotational motions is:

where
is the net torque applied to the object
I is the moment of inertia
is the angular acceleration
In this problem we have:
(net torque, with a negative sign since it is a friction torque, so it acts in the opposite direction as the motion)
is the moment of inertia
Solving for
, we find the angular acceleration:

Answer:
Explanation:
The person will exert a much larger force to take a fish out of the water than the fish itself weighs. The advantage of the fishing pole, however, is that it moves the fish a large distance, from the water to the boat or the shore.
Let the time be t.
so,In time t , distance travelled by 1st cyclist = 12.6 t
distance travelled by 2nd cyclist = 9.2t + 0.5 (1.5) t^2
Now, cyclist 1st is already 11.4 m ahead of 2nd cyclist.
so, 9.2t + 0.5 (1.5) t^2 = 11.4 + 12.6t
find t :
t = 6.77 sec