Question

Парашютист, достигнув в затяжном прыжке скорости 55 м/с, раскрыл парашют, после чего за 2 секунды его скорость уменьшилась до 15 м/с. Найдите время торможения, если его масса 80 кг.

Answer 1

A=∆v/t=40/2=20 м/с кв
F=ma=80*20=1600 (H)

Answer 2

Calculating Deceleration Time for a Parachutist

To find the time it took for the parachutist to decelerate from a speed of 55 m/s to 15 m/s after opening the parachute, we can use the formula for acceleration:

Acceleration (a) = Change in velocity (Δv) / Time (t)

Given: Initial velocity (V0) = 55 m/s Final velocity (V) = 15 m/s Time (t) = 2 seconds Mass (m) = 80 kg

Using the formula, we can rearrange it to solve for time: Time (t) = Change in velocity (Δv) / Acceleration (a)

The acceleration can be calculated using the formula: Acceleration (a) = Change in velocity (Δv) / Time (t)

Substitute the given values: Acceleration (a) = (15 m/s - 55 m/s) / 2 s

Let's calculate the acceleration first.

Calculating Acceleration

Using the given values: Acceleration (a) = (15 m/s - 55 m/s) / 2 s Acceleration (a) = -40 m/s / 2 s Acceleration (a) = -20 m/s²

The negative sign indicates that the acceleration is in the opposite direction of the initial velocity.

Calculating Time

Now, we can calculate the time using the acceleration we found: Time (t) = Change in velocity (Δv) / Acceleration (a) Time (t) = (15 m/s - 55 m/s) / -20 m/s² Time (t) = -40 m/s / -20 m/s² Time (t) = 2 s

Therefore, the time it took for the parachutist to decelerate from a speed of 55 m/s to 15 m/s after opening the parachute is 2 seconds.