An object of mass 40 kg is raised to a height of 5 m above the ground. What is its potential energy? If the object is allowed to fall, find its kinetic energy when it is half-way down.
Answers
pe=mgh
m=40kg
h=5m
g=10m/s
40x10x5
2000J IS THE ANSWER.
HOPE IT HELPS YOU.
Mass (m) = 40 kg
Acceleration due to gravity (g)= 10m/s²
Height (h)= 5m
Potential energy= m × g× h
P.E= 40 × 10 × 5 = 2000J
Potential energy = 2000J ( 2000 joules)
At a height of 5 metre object has a VG potential energy of 2000 J.
When this object is allowed to fall and it is Half way down its height above t.5m.
P.E at Half way down= m× g×h
P.E= 40× 10 × 2.5= 1000J
[h= 2.5 m]
1
Secondary SchoolPhysics 5 points
An object of mass 40 kg is raised to a height of 5 m above the ground. What is its potential energy? If the object is allowed to fall, find its kinetic energy when it is half-way down
NCERT Class IX
Sciences - Main Course Book
Chapter 11. Work and Energy
Ask for details Follow Report by ChiranjeeviSharaf598 21.05.2015
Answers
nikitasingh79
nikitasingh79 Genius
Given:
Mass (m) = 40 kg
Acceleration due to gravity (g)= 10m/s²
Height (h)= 5m
Potential energy= m × g× h
P.E= 40 × 10 × 5 = 2000J
Potential energy = 2000J ( 2000 joules)
At a height of 5 metre object has a potential energy of 2000 J.
When this object is allowed to fall and it is Half way down its height above the ground will be half of 5 m= 5/2= 2.5m.
P.E at Half way down= m× g×h
P.E= 40× 10 × 2.5= 1000J
[h= 2.5 m]
Potential Energy at Half way down= 1000 joules.
According to law of conservation of energy:
Total potential energy= potential energy at Half way down+ kinetic energy at Half way of a down
2000 = 1000 + K.E at Half way down
K.E at Half way down= 2000- 1000= 1000J
Kinetic energy at half way down= 1000 joules.