# Physics

How much work must be done to stop a 1250 kg car traveling at 105 km/h?

1. 👍
2. 👎
3. 👁
1. Work is Force multiplied by distance.
1250*105=?

1. 👍
2. 👎
2. So then you have to convert it to joules?

1. 👍
2. 👎
3. 131,250

1. 👍
2. 👎
4. 531684.027J

1. 👍
2. 👎
5. you will first of all conevert km/h to m/s which is 105 multiply 1000 then divide by 3600= 29.7.
use the formula f= ma.
1250 multiply by 9.8=12250
then use formula for work
w=f multiply by distance
w=12250 multiply by 29.7=363825J.

1. 👍
2. 👎
6. 5.3x〖10〗^5 J

1. 👍
2. 👎
7. physics

1. 👍
2. 👎
8. -531685J

1. 👍
2. 👎
9. First convert km/h to m/s because we need the answer to be J, which is Kg/m^2/s^2
105km/h=29.2 m/s (the rule is, to go from km/h to m/s is divide by 3.6)
W=1/2mv^2
W=(0.5)(1250)(29.2)^2
W=531684J
AND, because the work is being done to slow something down, it is negative.
So the answer is -531684J. (the comment above me is correct, I just wanted to provide an explanation for anyone who wanted to know how he/she above me got to the correct answer)

1. 👍
2. 👎

## Similar Questions

1. ### calc

a) A car is traveling at 50 mi/h when the brakes are fully applied, producing a constant deceleration of 40 ft/s^2. What is the distance covered before the car comes to a stop? b) A car braked with a constant deceleration of 40

2. ### physics

a)Two cars are traveling along a straight line in the same direction, the lead car at 24.5m/s and the other car at 29.6m/s. At the moment the cars are 41.6m apart, the lead driver applies the brakes, causing her car to have an

3. ### PHYSICS-URGENT HELP

A stationary police car emits a sound of frequency 1200 Hz that bounces off of a car on the highway and returns to the police car with a frequency of 1250 Hz. The police car is right next to the highway, so the moving car is

4. ### Physics Part A HELP!!

4.) In coming to a stop, a car leaves skid marks 80m long on the highway. Assuming a DEceleration of 7.00 m/s^2 (m/s/s), estimate the speed of the car just before breaking. 6.) A car traveling @ 90km/h strikes a tree. The front

1. ### math

The stopping distance d of a car after the brakes have been applied varies directly as the square of the speed r. If a car traveling 40 mph can stop in 100 ​ft, how fast can a car travel and still stop in 256 ​ft?

2. ### Physics

A 1250 kg car travelling at 60.0 km/h comes to a sudden stop in 35 m. What is the coefficient of friction acting on the brakes?

3. ### Math

The distance require to stop a car varies directly as the square of its speed. If 250 feet are required to stop a car traveling 60 miles per hour, how many feet are required to stop a car traveling 96 miles per hour!

4. ### Science halp

6.Two cars with different masses travel at the same speed down a hill toward a stop sign. What will happen when both cars apply brakes at the same time to stop? * A. The car with the smaller mass will require less force to stop

1. ### engg

a test car of mass 1250 kg is traveling at a speed of 72 kmph, when it is suddenly braked by locking the wheels. the average vehicle comes to a stop in a distance of 50 m. skid resisting force is.

2. ### math

The stopping distance (s) of a car varies directly as the square of its speed (v). If a car traveling at 50 mph requires 170 ft to stop, find the stopping distance for a car traveling at v2 = 55 mph.

3. ### Physics

A 1500 kg car traveling at 100 km/h west collides with a 1200 kg car traveling east at 85 km/h. The heavier car slows to 25 km/h after the collision. How fast is the lighter car traveling after the two cars collide?

4. ### Calculus, AntiDerivatives

I need help with this problem: A car traveling at 43 ft/sec decelerates at a constant 5 ft per second squared. How many feet does the car travel before coming to a complete stop? I'm not sure where to start, i know how to find