Bob pushes on a frictionless cart of mass 12.5 kg and the cart has an acceleration of 11.3 m/s². If his friend Bill pushes twice as hard on an identical cart, what will be the acceleration (in m/s²)? Your Answer: Answer

A drag chute must be designed to reduce the speed of a 1171 kg dragster from 342 km/hr to 80 km/hr in 4 seconds. Assume that the drag force is proportional to the velocity (kv). a) What value of the drag coefficient k is needed to accomplish this? kg · s? (Leave an exact answer.) m2 k = b) How far (in meters) will the dragster travel in the 4-sec interval? d = meters. (Round to the nearest meter) Question Help: O Message instructor Submit Question

Mary applies a force of 71 N to push a box with an acceleration of 0.45 m/s2. When she increases the pushing force to 79 N, the box's acceleration changes to 0.63 m/s2. There is a constant friction force present between the floor and the box.   (a)What is the mass of the box in kilograms? ?kg   (b)What is the coefficient of kinetic friction between the floor and the box?

G=25

A block is sliding along a frictionless surface at 11.1 m/s.  The block slides down a hill.  At the bottom of the hill, the block is sliding at 36.5 m/s.  How tall (in meters) is the hill?

A 1.4 gram bullet is shot into a tree stump. It enters at a velocity of 341 m/sec and comes to rest after having penetrated the stump in a straight line. It takes 0.00032 sec to come to a stop after striking the stump. What was the force on the bullet during impact?  (answer in Newtons)

A 1,865.66 kg car at rest at the top of a hill 20 m high is given a nudge and begins to roll down the hill.  It rolls up a 8.39 m hill on the other side.  How fast is it moving as it tops the lower hill?

The muzzle velocity of a typical 500 g spud is 25 m/s . The force given by the spud is K/(x+.09) where x is the distance of the barrel in meters. If the length of the barrel is 75 cm, what is the constant K? What is the force on the spud?

A car (mass 1000 kg) is traveling at 60 mph (26.82 m/s) when the driver notices a cat 50 m ahead in the road. Wanting to save the feline's life, the driver slams on the brakes and comes to a stop 2 m in front of the cat. What was the car's acceleration as it was braking?

A commercial airplane is coming in for a landing. Just before it hits the runway it is moving at 76 m/s. The plane has a mass of 20,000 kg. The runway is 1.6km long and, obviously, the airplane needs to be stopped before it reaches the end of the runway. How large is the braking force the airplane needs to stop safely before the end of the runway?