Answer:
a)
, b)
, c)
.
Explanation:
a) Let assume that car travel on a horizontal surface. The equations of equilibrium of the car are:


After some algebraic handling, the following expression for the propulsion force is constructed:



b) The power require to move the car at a speed of 5 meters per second is:



c) The efficiency of the car is:


Answer:
If an object moves twice as fast its kinetic energy quadruples.
Explanation:
The kinetic energy (K₁) of a body of mass (m) that moves with speed (v) is:
K₁= 1/2 * m* v²
If we double the speed of the body, its kinetic energy (K₂) will be:
K₂= 1/2 * m*( 2v)²
K₂= 1/2 * m* 4 *v²
K₂= 4(1/2 * m *v²)
K₂= 4*K₁
Something hot like a fire , an eye of a stove , and the sun