m = Mass of the refrigerator to be moved to third floor = 136 kg
g = Acceleration due to gravity by earth on the refrigerator being moved = 9.8 m/s²
h = Height to which the refrigerator is moved = 8 m
W = Work done in lifting the object
Work done in lifting the object is same as the gravitational potential energy gained by the refrigerator. hence
Work done = Gravitation potential energy of refrigerator
W = m g h
inserting the values
W = (136) (9.8) (8)
W = 10662.4 J
Answer:
22.05 Kg
Explanation:
Apply the formula:
GPE = Gravity . Mass . ΔHigh
2778.3 = 10 . Mass . 12.6
2778.3 = 126 . Mass
Mass = 2778.3/126
Mass = 22.05
The average force on the ball by the racket is 98 N. The correct option is the third option - 98 N
From the question, we are to determine the average force on the ball by the racket.
From the formula,

Where F is the force
m is the mass
v is the velocity
and t is the time
From the given information
m = 0.07 kg
v = 56 m/s
t = 0.04 s
Putting the parameters into the formula,
we get


F = 98 N
Hence, the average force on the ball by the racket is 98 N. The correct option is the third option - 98 N
Learn more on calculating force exerted on an object here: brainly.com/question/13590154
Answer:
1. Hydrogen
Atomic # = 1
Atomic Mass = 1.00794 ( If you round it it's 1.008 )
# of protons = 1
# of neutrons = none
# of electrons = 1
The answer is up . tylrhscjwizn