A1.20x10^3 kilogram car is traveling east at 25 meters per second. the brakes are applied and the car is brought to rest in 5.00 seconds answer
what is the magnitude of the horizontal net force that is required to bring it to a halt in a distance of 50.0m

Visualize the problem and identify special cases first examine the problem by drawing a picture and visualizing the motion. apply newton's 2nd law, ∑f⃗ =ma⃗ , to each body in your mind. don't worry about which quantities are given. think about the forces on each body: how are these consistent with the direction of the acceleration for that body? can you think of any special cases that you can solve quickly now and use to test your understanding later? one special case in this problem is if m2=0, in which case block 1 would simply fall freely under the acceleration of gravity: a⃗ 1=−gj^.

The cheetah is considered the fastest running animal in the world. cheetahs can accelerate to a speed of 20.1 m/s in 2.50 s and can continue to accelerate to reach a top speed of 28.1 m/s. assume the acceleration is constant until the top speed is reached and is zero thereafter.1) starting from a crouched position, how long does it take a cheetah to reach its top speed? (express your answer to three significant figures.) s2) how far does it travel in that time? (express your answer to three significant figures.) m3) if a cheetah sees a rabbit 120 m away, how long will it take to reach the rabbit, assuming the rabbit does not move? (express your answer to three significant figures.)

The molecular weight of oxygen gas (o2) is 32 while that of hydrogen gas (h2) is 2. prove that under same physical conditions, the velocity of sound in hydrogen is four times that in oxygen