Ch3HVN #2 Due Wednesday 1. A car\'s velocity decreases from 36 m/s to 14 m/s in
ID: 1884284 • Letter: C
Question
Ch3HVN #2 Due Wednesday 1. A car's velocity decreases from 36 m/s to 14 m/s in 3.5 s. What is its acceleration? 2. A driver comes to a stop in 2.4 seconds if his acceleration rate is -7.2 m/s', what was his initial speed? 3. A ball with a velocity of 4.5 m/s accelerates at 9.8 m/s'. What will its velocity be after 6.0 s? 4. How long will it take a cyclist to go from rest to 5.5 m/s if he accelerates at 0.70 m/s'? 5. What is the acceleration of a car that is moving at 25 m/s that comes to a stop in 185 6. How fast will a sports car be traveling in 8.0 sec if it has an acceleration of 16 m/s and its initial speed was 9.0 m/s? A bullet accelerates as it travels down the barrel of a gun. If it leaves the barrel at a speed of 575 m/s and it takes 0.15 sec what is its acceleration? 7. It takes a truck 12.5 s to come to a complete stop. If the truck can decelerate at a rate of 2.3 m/s', how fast was it initially traveling? 8. A runner takes off at the sound or the starting gun and gets to a speed of 8.3 m/s in 15 s. What is her acceleration? 9. 10. A cheetah can go from 4.8 m/s to 8.4 m/s with an acceleration of 6.4 m/s. How much time will this take?Explanation / Answer
Q1.
acceleration=(final speed-initial speed)/time
=(14-36)/3.5
=-6.2857 m/s^2
Q2. final speed=0
initial speed=final speed-acceleration*time
=0-(-7.2)*2.4
=17.28 m/s
Q3.
velocity after 6 seconds=initial velocity+acceleration*time
=4.5+9.8*6
=63.3 m/s
Q4.
time taken=(final speed-initial speed)/time
=(5.5-0)/0.7
=7.8571 seconds
Q5.
acceleration=(final speed-initial speed)/time
=(0-25)/1.8
=-13.889 m/s^2
Q6.final speed=initial speed+acceleration*time
=9+16*8
=137 m/s
Q7.
acceleration=(final speed-initial speed)/time
=(575-0)/0.15
=3833.3 m/s^2
Q8.
final speed=0
initial speed=final speed-acceleration*time
=0-(-2.3)*12.5
=28.75 m/s
Q9.acceleration=(final speed-initial speed)/time
=(8.3-0)/15
=0.55333 m/s^2
Q10.
time taken=(final speed-initial speed)/acceleration
=(8.4-4.8)/6.4
=0.5625 seconds