The car is moving at a speed of 10 m / s. For its kinetic energy to double, the speed of the car must be?

First, let’s write down the formula for kinetic energy:
Ek = (m * v ^ 2) / 2
Where m is the mass of the body, v is its speed.
The car is moving at a speed of 10 m / s. We cannot find the kinetic energy of cars at this speed, due to lack of data (not enough car mass), but knowing the formula, we can find out how it can change.
Substituting this speed into the formula, we get that Ek = (m * 100) / 2
Imagine that Ek is X, then we have to find the change in speed, at 2X. Then:
2X = (m * 100 * 100) / 2
2X = (m * 10000) / 2
We can see that the speed in this formula has become equal to 10,000, but let me remind you that it is given in the square. Hence, the root of 10000 = 100.
100 m / s – the required vehicle speed to increase its kinetic energy.
Answer: 100 m / s.