Question

Bonny Blair of the United States set a world record in speed skating when

she skated 5.00 x 10' m with an average speed of 12.92 m/s. Suppose
Blair crossed the finish line at this speed and then skated to a stop. If the
work done by friction over a certain distance was -2830 J, what would
Blair's kinetic energy be, assuming her mass to be 55.0 kg.

Answer 1

To calculate Blair's kinetic energy, we can use the formula: Kinetic Energy = 0.5 * mass * velocity^2. Given her mass and average speed, we can substitute these values into the formula to find her kinetic energy.

Step-by-step explanation:

To calculate Bonny Blair's kinetic energy, we can use the formula:

Kinetic Energy = 0.5 * mass * velocity^2

Given that her mass is 55.0 kg and her average speed is 12.92 m/s, we can substitute these values into the formula:

Kinetic Energy = 0.5 * 55.0 kg * (12.92 m/s)^2

Calculating this expression gives us Blair's kinetic energy, which can be used to determine the amount of work done by friction over a certain distance.

Answer 2

4589.75J

Step-by-step explanation:

Kinetic energy = 1/2 x M x v^2

Given

Mass M = 55.0kg

V = 12.92m/s

Kinetic energy

= 1/2 x 55.0 x (12.92)^2

= 1/2 x 55.0 x (12.92 x 12.92)

= 1/2 x 55.0 x 166.9

Multiply through

= 9179.5/2

= 4589.75J