Question
Find the force in newtons needed to slow a 2500 kg truck from 20 m/s to 10m/s in 100m. Hint:keep in mind the truck is slowing down.
Solution
3.8
(343 Votes)
Julian
Master · Tutor for 5 years
Answer
Here's how to solve this problem:1. **Find the acceleration:**We can use the following equation of motion to find the acceleration (a):v² = u² + 2asWhere:* v = final velocity (10 m/s)* u = initial velocity (20 m/s)* s = distance (100 m)* a = accelerationRearranging the equation to solve for 'a':a = (v² - u²) / 2sa = (10² - 20²) / (2 * 100)a = (100 - 400) / 200a = -300 / 200a = -1.5 m/s² (The negative sign indicates deceleration, which is expected since the truck is slowing down.)2. **Calculate the force:**Now we can use Newton's second law of motion:F = maWhere:* F = force* m = mass (2500 kg)* a = acceleration (-1.5 m/s²)F = 2500 kg * (-1.5 m/s²)F = -3750 NThe force is -3750 N. The negative sign indicates that the force is acting in the opposite direction of the truck's motion, which is what causes it to slow down. Therefore, the force needed to slow the truck is 3750 N.