Question

If the speed of a motor scooter doubles, which of the following also doubles? 1)kinetic energy 2) acceleration 3) momentum 4) all of the above

Answer 1

Answer:

3

Explanation:

-The formula for kinetic energy is the following:

K.E.=$\frac{1}{2}$m$v^{2}$

where:

K.E. is kinetic energy

m is mass

v is velocity

Here we can see that kinetic energy is proportional to the velocity squared, so if the speed or velocity of the scooter doubles then this would quadruple its kinetic energy.

-The acceleration is the rate of change of velocity per unit of time. A scooter could double its speed with a constant acceleration, so an increase in speed doesn't necessarily mean an increase in acceleration.

-The formula for momentum is the following:

p=mv

where:

p is momentum

m is the mass of the object

v is the objects velocity

Here we can see that the momentum is directly proportional to the velocity, so if the scooter where to double its velocity then it would also double its momentum.