How much work must be done to stop a 970 kg car traveling at 115 km/h?

Convert that velocity to meters per second. Then calculate (1/2)MV^2, the kinetic energy (KE). V must be in m/s and the mass M in kg, to get the KE in Joules.

The car must perform an equal amount of work if it is to lose that kinetic energy.

If you are stopping the car, the amount of work that must be performed is a negative number equal to the initial kinetic energy.

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To calculate the work required to stop a car, we need to consider the car's initial kinetic energy and its final kinetic energy when it comes to a stop.

The initial kinetic energy (KE) of the car is given by the formula KE = (1/2) mv², where m is the mass of the car and v is its velocity.

In this case, the mass of the car is 970 kg and its velocity is 115 km/h. First, we need to convert the velocity from km/h to m/s as follows:

115 km/h * (1000 m/1 km) * (1 h/3600 s) = 31.94 m/s

Now, we can calculate the initial kinetic energy:

KE_initial = (1/2) * 970 kg * (31.94 m/s)²

Next, since the car comes to a stop, its final velocity will be zero. The final kinetic energy (KE_final) will also be zero.

The work done to stop the car is equal to the change in kinetic energy, which can be calculated as:

Work = KE_final - KE_initial

Since KE_final is zero, the work done to stop the car is equal to -KE_initial, representing the negative change in kinetic energy.

Now, plugging in the values:

Work = 0 - (1/2) * 970 kg * (31.94 m/s)²

Calculating this will give you the amount of work that must be done to stop the car.