A car weighing 3 tons moves at a speed of 28.8 km / h. when braking, stops in 6 seconds. Find the braking force.
To solve, you first need to write down the letter formula of Newton’s Second Law, where:
F is the force that acts on the car when braking
a – acceleration (according to the condition of the problem, braking);
m is the mass of the object (in this case, the weight of the car);
V – initial speed of movement of the object
V0 is the final speed of the object;
t is the braking time.
F = m * a.
The amount of deceleration can be expressed in terms of the ratio of speed and time.
Since the final speed is 0, we exclude it.
F = m * (V – V0) / t.
If we substitute the values from the condition into this formula, we get:
F = 3 * 28.8 / 6 = 86? 4/6 = 14.4 kN.
We write down the value of the force in kN, since the weight of the car is indicated in tons.
1 ton = 1000 kilograms.
When converted to Newtons, we get:
F = 14.4 * 100 = 14400 N.
Answer:
A force equal to 14,400 Newtons acts on the car when braking.