Which has the highest PE?
A 1.1 kg squirrel in a tree 10.0 m from the ground
A 0.22 kg bird in a tree 20.0 m from the ground
A 2.0 kg chipmunk in a tree 5.0 m from the ground
Mr. C (65 kg) who is levitating at 15 cm from the ground
The squirrel
Which has more ME?
Mr. C walking on a bridge
Mr. C running on a bridge
Mr. C walking on the ground
Mr. C running on the ground
Mr. C running on a bridge
Mr. C drops a 1.0 kg ball from 1.0 m high, what is its max KE during the fall?
9.8 J
Solve for original ME at station 1 (3SF)
1,960 J (or 1.96 KJ)
we just call it "g", what's it's value with units?
9.8 m/s2
SI base units for PE (the answer is not Joules)
kg*m2/s2
How much mechanical energy in Joules does an object have if it has 0.50 kJ potential and 10 J kinetic energy?
500 J (510 J in 1 SF)
Mr. C drops a 1.0 kg ball from 1.0 m high, what is its max velocity during the fall?
4.4 m/s
Calculate the velocity at station 3 (3SF)
8.85 m/s
Term for when a freefalling object has air resistance = g
Terminal Velocity
PE of a 10 kg object that is on a ledge 10 m from the ground
1000 J (980 J with 1 SF)
A rock is on a cliff. It falls to the ground below. At which point is KE = PE during the fall?
Halfway down from the top of the cliff to the ground below
A 5.0 kg projectile has 36 J of KE & a ME of 73 J, calculate the velocity
3.8 m/s
Calculate the KE at station 4
900 J
We call g a constant, but its actually varies. Where on earth is g the highest?
At the north / south poles
An object is hanging from a hook 15 m above the ground. If it has a PE of 970 J, what is its mass?
6.6 kg
How much mechanical energy does an object have if it is 10.0 kg, 10.0 m above the ground and is freefalling at a velocity of 10.0 m/s?
1,480 J (or 1.48 KJ)
Mr. C drops a 12.0 kg ball from 7.0 m high, what is its max velocity during the fall?
12 m/s
Calculate the velocity at station 2 (3SF)
4.43 m/s
Which planet has the smallest g (don't say Pluto)
Mercury
An empty 3,300 kg elevator is 24 m above the ground level when its cables snap. What will be its maximum velocity as it falls down?
22 m/s
A 750 g object is pushed off a 175 m cliff. When it is 75 m from the bottom, how much ME does the object have?
1,300 J (or 1.3 kJ)
A 750 g object is pushed off a 175 m cliff. When it is 75 m from the bottom, what is the velocity of the object?
44 m/s
Calculate the height at station 4 (3 SF)
2.16 m
Though it was more than opne person that contributed to this discovery, who is credited most for measuribng / calculating g?
Galileo Galilei