WORK AND ENERGY
MECHANICAL ENERGY
HEAT
ME PROBLEMS
100
Analyze the diagram. Is the Force (F) la indicated in blue generating Work?
No, since is perpendicular to the motion (d)
100
International System Measurement Unit for Energy
Joules (J)
100
A unit to determine Energy which is equivalent to the Specific Heat of Water
Calorie
100
Where is the point of Maximum Kinetic Energy?
Point C
200
Friction Force (Ff) is typically a force that opposes the direction of displacement (d). This will result in:
a) No Work
b) Negative Work
c) Positive Work
b) Negative Work, since is parallel to motion but goes in the opposite direction
200
It's an example of an External Force.
a) Gravity b) Friction c) Weight d) Electric Force
b) Friction
200
1 Cal = 4.814 J.
Convert 40 Cal to J
192.6 J
200
Apart from Point A, at which point the PE has the same Value?
Point D
300
Is the following an example of Positive Work?
Yes, since the Force pushes on the same direction as the motion.
300
The Mechanical Energy of an object at rest with a given height equals to its:
a) Potential Energy
b) Kinetic Energy
c) Heat Energy
a) Potential Energy
300
It is defined as the sum of Kinetic Energy from particle's motion on a System.
a) Heat
b) Thermal Energy
c) Temperature
b) Thermal Energy
300
Assuming there are no External Forces on this System. Calculate the PE at Point B.
0.4 J. PE= ME-KE
400
A Force of 300 N pushes on a given direction to cause a displacement of 8 m. How much is the Work (W)?
2400 J. W=Fd
400
When it comes to Energy Conservation, it's when Energy moves across Systems.
a) Transfer
b) Transformation
c) Transport
a) Transfer
400
When two systems at different temperatures exchange Thermal Energy, both systems will:
a) Absorb energy
b) Lose energy
c) Transfer heat until Thermal equilibrium is reached
d) Transport energy into an external system
c) Transfer heat until Thermal equilibrium is reached
400
Assuming the mass of this object is 0.8 kg. Calculate the height (h) at point D. Express the result with one decimal number.
0.3 m. h= PE/m x g
500
An object falling generates a Work of 4,000 J when it falls through the first 10 m. How much is the Force of Weight?
400 N. F= W/d
500
Energy from the Sun reaches the Earth, this is an example of:
a) Transfer
b) Transformation
c) Transport
c) Transport
500
It is defined as the amount of Energy transfer necessary to raise the temperature of a substance by 1°C.
Specific Heat
500
Assuming the mass of this object is 0.8 kg. Calculate the Speed (v) at point C. Express the result with one decimal number.
v = 2.5 m/s. KE = √KE x 2/m