Question

Автомобиль массой 1 т начинает и через 5 с останавливается какой была скорость автомобиля в начале торможения если сила сопротивления движению составляет 4000н

Answer 1

A=F/m=4000/1000=4 м/с2
V=V0-a*t   V=0
V0=a*t=4*5=20 м/с

Answer 2

Calculation of Initial Velocity

To calculate the initial velocity of the car before it starts braking, we can use the equation of motion:

v = u + at

Where: - v is the final velocity (which is 0 m/s since the car comes to a stop) - u is the initial velocity (what we want to find) - a is the acceleration (which can be calculated using the force of resistance and the mass of the car) - t is the time taken to come to a stop (given as 5 seconds)

The force of resistance is given as 4000 N, and the mass of the car is 1 ton, which is equivalent to 1000 kg.

Using the equation of motion, we can rearrange it to solve for the initial velocity:

u = v - at

Substituting the given values:

u = 0 - (4000/1000) * 5

Simplifying the equation:

u = -20 m/s

Therefore, the initial velocity of the car before it starts braking was -20 m/s. The negative sign indicates that the car was moving in the opposite direction of the force of resistance.