A car is traveling on a straight, level road under wintry conditions. Seeing a patch of ice ahead of her, the driver of the car slams on her brakes and skids on dry pavement for 70 m, decelerating at 6.0 m/s2. Then she hits the icy patch and skids again. The car takes a duration of 85.0 s to come to rest during the second skid. If her initial speed was 50 m/s, what was the magnitude of the deceleration on the ice during the second skid. 1. Which of the following kinematic equations would you use to determine the velocity of the car after skidding on the dry pavement for 70 m? 2. Determine the velocity of the car after skidding on the dry pavement for 70 m. 3. Which of the following kinematic equations would you use to determine the deceleration of the car after skidding to a stop on the icy patch?   4. Determine the magnitude of the deceleration of the car after skidding to a stop on the icy patch

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A 500kg car moving to the north at 45m/s crashes head-on into a 600kg car that is moving the south at 23m/s. When they crash, they stick together. At what velocity do the two cars move after the collision?

As a city planner, you receive complaints from local residents about the safety of nearby roads and streets. One complaint concerns a stop sign at the corner of Pine Street and 1st Street. Residents complain that the speed limit in the area (55 mph) is too high to allow vehicles to stop in time. Under normal conditions this is not a problem, but when fog rolls in visibility can reduce to only 155 ft. Since fog is a common occurrence in this region, you decide to investigate. The state highway department states that the effective coefficient of friction between a rolling wheel and asphalt ranges between 0.689 and 0.770, whereas the effective coefficient of friction between a skidding (locked) wheel and asphalt ranges between 0.450 and 0.617. Vehicles of all types travel on the road, from small VW bugs weighing 1210 lb to large trucks weighing 8640 lb. Considering that some drivers will brake properly when slowing down and others will skid to stop, calculate the minimum and maximum…

You purchase a used car.  After handing over the cash, you drive it away from the lot, starting at rest and accelerating at 19.8 m/s2.  After 16.9 s, the engine breaks down and it decelerates at 5.9 m/s2 until coming to a stop.  How far were you able to drive the car? (Please answer down to the fourth decimal place- i.e 10.3456)

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.)

An initially motionless test car is accelerated uniformly to 135 km/hr in 8.08 seconds before striking a simulated deer. The car is in contact with the faux fawn for seconds, after which the car is measured to be traveling at 87.5 km/hr. What is the magnitude of the average acceleration of the car during the collision?

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?

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.

Acceleration is sometimes expressed in multiples of g, where g = 9.8 m/s2 is the magnitude of acceleration due to the earth's gravity. In a test crash, a car's velocity goes from 26 m/s to 0 m/s in 0.15 s. How many g's would be experienced by a driver under the same conditions?