Answer:

Explanation:
The minimum total work is the work needed to counteract the work associated with the weight:




Answer:
1626.4 N
Explanation:
Given that a 82 kg man, at rest, drops from a diving board 3.0 m above the surface of the water and comes to rest 0.55 s after reaching the water. What force does the water exert on him?
The parameters to be considered are:
Distance S = 3m
Time t = 0.55s
Since the man started from rest, initial velocity u = 0
Using second equation of motion
S = Ut + 1/2at^2
3 = 1/2 × a × 0.55^2
3 = 1/2 × a × 0.3025
a = 3/ 0.15125
a = 19.83 m/s^2
Force = mass × acceleration
Force = 82 × 19.83
Force = 1626.4 N
Therefore, the force that water exerted on him is 1626.4 N
The car will move in a speed of 45 meter per second
Answer:
111.5 m
Explanation:
Given that You are driving to the grocery store at 14 m/s. You are 115 m from an intersection when the traffic light turns red. Assume that your reaction time is 0.50 s and that your car brakes with constant acceleration.
Use first equation of motion
V = U - at
Since the car is going to rest, V = 0 and a = negative
0 = 14 - a × 0.5
0.5a = 14
a = 14 /0.5
a = 28 m/s^2
Let us use second equation of motion
S = Ut - 1/2at^2
S = 14 × 0.5 - 0.5 × 28 × 0.5^2
S = 7 - 3.5
S = 3.5 m
115 - 3.5 = 111.5
Therefore, you are 111.5 metres from the intersection (in m) when you begin to apply the brakes.
Answer: Well the answer is KE = 5.625E-7 i just don't know the units for it...
Hope this helps....... Stay safe and have a Merry Christmas!!!!!!!!!! :D