Answer:
Ben's average speed was twice Debby's average speed.
Explanation:
Ben covered a total distance of 16 miles (10+4+2) and Debby covered 8 miles (3+2+2+1) which is half of what Ben covered. As they both reached the place in the same amount of time it tells us Ben was faster.
First I’ll show you this standard derivation using conservation of energy:
Pi=Kf,
mgh = 1/2 m v^2,
V = sqrt(2gh)
P is initial potential energy, K is final kinetic, m is mass of object, h is height from stopping point, v is final velocity.
In this case the height difference for the hill is 2-0.5=1.5 m. Thus the ball is moving at sqrt(2(10)(1.5))=
5.477 m/s.
Answer:
11.27N
Explanation:
Given parameters:
Mass of the book = 1.15kg
Unknown:
Magnitude of the normal force = ?
Solution:
The normal force is the vertical force exerted by a body on an object.
It can be described as the weight of an object.
Normal force = mass x acceleration due to gravity
Normal force = 1.15 x 9.8 = 11.27N
Fnet = (mass) (acceleration)
= 11 kg x 3.7m/s^2
= 41 N