Answer:
Explanation:
Samantha walks along a horizontal path in the direction shown the curved path is a semi circle with a radius of 2 m while the horizontal part is for me what is the magnitude of displacement
Displacement is given by the straight line distance between P and Q. Displacement will be length of straight line joining P and Q
a semi circle with a radius of 2 m
Length of this straight line=4+diameter
=4+(2*2)
=8 m
1) The most potential energy is at position A
2) The most kinetic energy is at position C
Explanation:
1)
The gravitational potential energy is the energy possessed by an object due to its position in a gravitational field, and it is given by the equation
where
m is the mass of the object
g is the acceleration of gravity
h is the height of the object relative to the ground
From the equation, we see that the potential energy is directly proportional to the heigth of the object: therefore, the roller coaster in this problem will have the most potential energy at its highest postion, so at position A.
2)
The total mechanical energy of the roller coaster at any point along the track is given by
where
PE is the potential energy
KE is the kinetic energy
Assuming there is no friction, the mechanical energy E is constant. This means that when PE increases, KE decreases, and when PE increases, KE decreases.
Therefore, the cart will have maximum kinetic energy when the potential energy is at minimum: and since the potential energy is directly proportional to the height of the track, this will occur at the lowest position, so at position C.
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A free-falling object is an object moving under the effect of gravitational forces alone
The correct option to select for the True or False question is False
The reason the above selected option is correct is as follows:
According to Newton's second law of motion, we have;
Force = Mass × Acceleration
The force of gravity is
Where;
m = The mass of the object
∴ The force acting on an object in free fall, = m × g
Therefore the acceleration of an object in free fall is the constant acceleration due to gravity, and it therefore, does not change with time
The correct option for the question, acceleration of a free-falling object in a frictionless environment increases as a function of time is <u>False</u>
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Answer:
The same amount of energy is required to either stretch or compress the spring.
Explanation:
The amount of energy required to stretch or compress a spring is equal to the elastic potential energy stored by the spring:
where
k is the spring constant
is the stretch/compression of the spring
In the first case, the spring is stretched from x=0 to x=d, so
and the amount of energy required is
In the second case, the spring is compressed from x=0 to x=-d, so
and the amount of energy required is
so we see that the amount of energy required is the same.