Answer:
c. 1600J
Explanation:
The loss in potential energy of the boy is given by:

where
m = 40 kg is the mass of the boy
g = 9.8 m/s^2 is the acceleration of gravity
is the total change in the height of the boy (4 metres + 2 cm due to the compression of the spring)
Substituting, we find

When a woman walks south at a speed of 2.0mph for 60 minutes. She then turns around and walks north at a distance of 3000m in 25 minutes. then the woman's average speed during her entire motion would be 73.15 meters /minute.
<h3>What is speed?</h3>
The total distance covered by any object per unit of time is known as speed.
the mathematical expression for speed is given by
speed = total; distance /total time
As given in the problem a woman walks south at a speed of 2.0mph for 60 minutes
60 min = 1 hour
1 mile = 1.60934 km
The distance covered by her southwards = speed ×time
=2 mph × 60 minutes
= 3.218 km
She then turns around and walks north at a distance of 3000m in 25 minutes
The distance covered northward is 3000m
speed = total distance /total time
=(3218 +3000) /(60+25)
=73.15 meters /minutes
Thus, The average speed of the woman would be 73.15 meters /minute.
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"The proton and neutron have nothing to do with the isotope little billy"
Answer:d
Explanation:
Alpha particles are heaviest among alpha, beta and gamma so they have least amount of Penetration compared to both.
Gamma Particles are lightest among three so they can Penetrate most .
The order of Penetration is given by
Alpha< Beta < Gamma
The momentum of the second ball was 15 kg.m/s.
<h3>What is inelastic collision?</h3>
In which collision some amount of kinetic energy of the system is lost that called inelastic collision. In purely inelastic collision, two bodies stick together. But principle of conservation of linear momentum is obeyed.
In the given question,
Two balls collide and after collision, the final momentum of the system = 18 kg.m/s.
Initial velocity of 1st ball of mass 3 kg is 1 m/s.
So, Initial momentum of first ball = mass × velocity = (3 kg) × (1 m/s) = 3 kg.m/s.
According to Principle of conservation of linear momentum for this inelastic collision,
Initial momentum of first ball + initial momentum of second ball = final momentum of the system
⇒ initial momentum of second ball = final momentum of the system - Initial momentum of first ball
= 18 kg.m/s - 3 kg.m/s.
= 15 kg.m/s.
Hence, initial momentum of second ball = 15 kg.m/s.
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