Question

Materials:

1. Foam Ball on Length of String
2. Stopwatch
3. Digital Scale
4. Meter Stick
Objective:
It is not always possible to directly measure the centripetal force applied to a rotating object. In
this lab, you will use the concepts of circular motion and Newton's laws to determine the
centripetal force applied to a ball rotating at the end of a string.
Procedure:
1. Measure and record the mass (in kilograms) of the foam ball.
kg
2. Measure the length of the string attached to the ball (measured to the center of the ball). This
will be the radius of your swing. Record it in the table below.
3. Swing the ball at a constant speed in a horizontal circle. Using the stopwatch, measure the
time it takes to make 10 complete revolutions. Divide the time by 10 to determine the period and
record it in the table below.
4. Calculate the velocity, acceleration, and centripetal force. Record the values in the table.
Radius (m) Circumference (m)
Period (s)
Velocity (m/s)
Centripetal
Acceleration (m/s²)
Centripetal Force (N)
Question:
Keeping the radius at the same value, will swinging the ball at a faster speed cause the centripetal
force to increase or decrease? Use the equation for centripetal force to explain your answer.
5. Verify your answer by swinging the ball at a higher speed. Measure the period as you did in
step 4 and calculate the new velocity, acceleration, and centripetal force. Record the results in
the table below.
Radius (m) Circumference (m) Period (s)
Velocity (m/s)
Centripetal
Acceleration (m/s²)
Centripetal Force (N)

Answer 1

When swinging a ball on a string, the centripetal force is the force that keeps the ball moving in a circular path. The centripetal force is directly related to the speed of the ball and inversely related to the radius of the circular path.

The equation for centripetal force is:

F = (m * v^2) / r

where F is the centripetal force, m is the mass of the ball, v is the speed of the ball, and r is the radius of the circular path.

Keeping the radius at the same value, if we increase the speed of the ball, the centripetal force will also increase. This is because the centripetal force is proportional to the square of the speed.

For example, let's consider a ball of mass 1 kg swinging on a string with a radius of 1 meter. If the ball is swinging at a speed of 1 m/s, the centripetal force would be:

F = (1 kg * (1 m/s)^2) / 1 m

F = 1 N

Now, if we increase the speed of the ball to 2 m/s while keeping the radius the same, the centripetal force would become:

F = (1 kg * (2 m/s)^2) / 1 m

F = 4 N

As you can see, the centripetal force has increased when the speed of the ball increased. This is because the force required to keep an object moving in a circular path increases with the square of the speed.

Therefore, when swinging the ball at a faster speed while keeping the radius constant, the centripetal force will increase