Highway safety engineers build soft barriers so that cars hitting them will slow down at a safe rate. A person wearing a safety belt can withstand an acceleration of 300 m per s2. How thick should barriers be to safely stop a car that hits a barrier at 110 km per h?

A 1000kg helicopter hovers over a forest fire and starts to squirt water downward with a speed of 10m/s at a rate of 40kg/s. What is the initial upward acceleration on the helicopter when it first starts to release the water

Upon impact, bicycle helmets compress, thus lowering the potentially dangerous acceleration experienced by the head. A new kind of helmet uses an airbag that deploys from a pouch worn around the rider’s neck. In tests, a headform wearing the inflated airbag is dropped onto a rigid platform; the speed just before impact is 6.0 m/s. Upon impact, the bag compresses its full 12.0 cm thickness, slowing the headform to rest. What is the acceleration, in g’s, experienced by the headform? (An acceleration greater than 60g is considered especially dangerous.)

A car starts from rest and accelerates at 2.1 m/s2 until it reaches a speed of 20 m/s.  The car then slows at 1.6 m/s2 until it stops.  How far does the car go?

A truck starts from rest and reaches a speed of 60km/h in 3 minutes. The acceleration of the truck is O a. 0.092 m/s? O b. 0.333 m/s? O c. 8.33 m/s² O d. 20 m/s?

The rocket sled starts from rest and accelerates at a = 30 + 2t m/s² until its velocity is 400 m/s. It then hits a water brake and its acceleration is a = -0.003v² m/s² until its velocity decreases to 100 m/s. What total distance sf does the sled travel?

I am also having trouble solving this problem since it includes the acceleration with its initial velocity without the final velocity. A car traveling with an initial velocity of 10 m/s accelerates at a constant rate of 2.2 m/s2 for 2 seconds.

Highway safety engineers design "soft" crash barriers so that cars hitting them will slow down at a safe rate. A person wearing a safety belt can withstand a deceleration rate of 300 m/s2. How thick should barriers be to safely stop a car that hits the barrier at 110 km/h and then slows to a stop as it crashes through and destroys the barrier?

An unwary football player collides with a padded goalpost while running at a velocity of 7.7 m/s and comes to a full stop after compressing the padding and his body 0.36 m. a) What is his acceleration? Careful with the sign! b) How long does the collision last?

A car traveling 89 km/h strikes a tree. The front end of the car compresses and the driver comes to rest after traveling 0.81 m. a) What was the average acceleration of the driver during the collision? b) Express the answer in terms of g.