After what time interval from the moment of start, the motorcyclist moving with constant acceleration a = 5m / s,

After what time interval from the moment of start, the motorcyclist moving with constant acceleration a = 5m / s, will develop a speed of V = 90km / h? At what distance from the starting point will this happen?

V0 = 0 m / s.

a = 5 m / s2.

V = 90 km / h = 25 m / s.

t -?

S -?

The acceleration of a body is a vector physical quantity that shows how the body’s speed changes over time. The acceleration of the body is determined by the formula: a = (V – V0) / t.

Since the initial speed of the motorcyclist is V0 = 0 m / s, the formula will take the form: a = V / t.

t = V / a.

t = 25 m / s / 5 m / s2 = 5 s.

With uniformly accelerated movement, the path S traveled by the motorcyclist is expressed by the formula:

S = V0 * t + a * t ^ 2/2.

Since it moves from a state of rest V0 = 0 m / s, the formula will take the form: S = a * t ^ 2/2.

S = 5 m / s2 * (5 s) ^ 2/2 = 62.5 m.

Answer: t = 5 s, S = 62.5 m.