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A footballer kicks a ball vertically upwards. Initially, the ball is stationary. His boot is in contact with the ball for 0.050s. The average resultant force on the ball during this time is 180N. The ball leaves his foot at 20m/s. Calculate the impulse

Impulse is Force x TimeThe force has been given as 180N. The time that the foot was in contact with the ball was 0.05sImpulse=FxtImpulse=180x0.05Impulse= 9Ns
SA
Answered by Sophia A. • Physics tutor
9987 Views

Name and describe both of Kirchhoff's laws.

The Loop rule, this states that the sum of the potentials in a loop must be equal to 0.The Junction rule, this states that the sum of the current entering the junction must be equal to the sum of the current...
BB
Answered by Boris B. • Physics tutor
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In the early 20th Century the plum pudding model of the atom was replaced by the nuclear model of the atom, explain why this happened.

The plum pudding model defined the atom as a particle in which the charge and the mass of the atom was spread evenly. An experiment was set up in which alpha particles where shot to a thin gold foil. The exp...
JP
Answered by Joel P. • Physics tutor
4782 Views

Explain why evaporation cools a liquid.

Evaporation occurs when the most energetic particles in a liquid have enough energy to overcome the attractive intermolecular bonds and leave the liquid. Because only the hughest energy particles evaporate t...
CK
Answered by Charlotte K. • Physics tutor
3308 Views

What is refraction?

Refraction is what occurs when light passes from one medium to another (for example, air to water) and because of the difference in the medium, the speed changes. This change in speed of light causes it to '...
TD
Answered by Tanika D. • Physics tutor
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