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PLZZZZZZZZZZ FOR GOD SAKE HELP ME

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A small coin of mass m is initially at rest. It is dropped from a height h above ground level.
The coin has a speed v as it hits the ground.
The gravitational field strength g is equal to 10N/kg.
(a) State an expression for:
• the gravitational potential energy of the coin at a height h above ground level
gravitational potential energy = .........................................................................................

• the kinetic energy of the coin when travelling at a speed v.
kinetic energy = .................................................................................................................[2] (b) The coin is dropped from the top of a building of height 380m.
Determine the speed of the coin as it hits the ground. You may ignore air resistance.

User UncleAdam
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1 Answer

14 votes
14 votes

Step-by-step explanation:

(a) The gravitational potential energy of the coin above the ground level is given by :


E=mgh

Where

m is mass of the object

g is acceleration

h is height

The kinetic energy of the coin when travelling at a speed v is given by :


E_k=(1)/(2)mv^2

(b) The coin is dropped from the top of a building of height 380m. Let v the speed of the coin as it hits the ground. Using the conservation of energy.


v=√(2gh) \\\\v=√(2* 9.8* 390) \\\\v=87.42\ m/s

Hence, this is the required solution.

User Ozgur Oz
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2.7k points