Answer:
Potential energy of book = 7.5 J
Explanation:
Given:
Weight of book = 5 N
Height of shelf = 1.5 meter
Find:
Potential energy of book
Computation:
Weight = Mass x Acceleration of gravity
Mass x Acceleration of gravity = 5 N
Potential energy = Mass x Acceleration of gravity x Height
Potential energy of book = Mass x Acceleration of gravity x Height
We know that;
Mass x Acceleration of gravity = 5 N
So,
Potential energy of book = 5 x 1.5
Potential energy of book = 7.5 J
The height attained by the ball is 11.86m
a ball is shot from the ground straight up into the air its initial and final velocity is
initial velocity, u = 50 ft/s = 50×0.305 = 15.25m/s
final velocity ,v = 0 m/s
gravity =-9.8 m/s²
( negative sign shows acceleration in opposite direction)
height =?
using the newton motion of equation
v² = u² + 2as
where
a= acceleration due to gravity(g)
s = height
v² = u² + 2gs
(0)² = (15.25)² + 2×(-9.8)×s
0 = (15.25)² - 19.6 × s
s= - (15.25)²/ 19.6
s = 11.86m
after ignoring the air resistance the maximum height of the ball is 11.86m
To learn more about motion under gravity -
brainly.com/question/27962354
#SPJ4
The answer is B.
This is because you add up all of the times (1.44s+1.70s+1.58s+1.76s) and you get 6.48 then you divide 6.48 by 4 to get the average of the times. Now you get the distance (200m) and because speed=distance/time you divide 200m/1.62s to get 123m/s. I hope this made sense :)