Gurumuda Networks
4 Net work Gravitational potential energy Kinetic energy – Problems and Solutions
1. A 5-kg object at the height of 10-meters above the ground. Acceleration due to gravity is 10 m/s2. What is the work done on the object to moves it upward to the height of 15-meters above the ground?
Known :
Mass of object (m) = 5 kg
Height (h) = 10 meters
Acceleration due to gravity (g) = 10 m/s2
Wanted: Work was done on the object to moves it upward to the height of 15-meters above the ground.
Moment of force – problems and solutions
1. If FR is the net force of F1, F2, and F3, what is the magnitude of force F2 and x?
Known :
Net force (FR) = 40 N
Force 1 (F1) = 10 N
Force (F3) = 20 N
Wanted: The magnitude of force F2 and distance of x
14 Boyle’s law Charles’s law Gay-Lussac’s law – Problems and Solutions
1. The air pressure of car’s tire is 432 kPa with the temperature of 15 oC. After several hours, the pressure of air is 492 kPa. If expansion ignored, what is the temperature of air in the tire?
Known :
Initial pressure (P1) = 432 kPa
Final pressure (P2) = 492 kPa
Initial temperature (T1) = 15 oC
Wanted: Final temperature (T2)
Carnot cycle – problems and solutions
1. If heat absorbed by the engine (Q1) = 10,000 Joule, what is the work done by the Carnot engine?
Known:
Low temperature (T2) = 400 K
High temperature (T1) = 800 K
Heat input (Q1) = 10,000 Joule
Wanted: Work done by Carnot engine (W)
Solution:
Manometer tube – problems and solutions
1. A manometer tube is filled with two type of liquids. The density of liquid 1 is ρ1 = 0.8 g.cm-3, and the density of liquid 2 is ρ2 = 1 g.cm-3, and height h1 = 10 cm, then what is the height of h2.
Known :
Density of liquid 1 = 0.8 g.cm-3
Density of liquid 2 = 1 g.cm-3
Height 1 = 10 cm
Wanted: Height 2
Mechanical energy – problems and solutions
The work-mechanical energy principle
1. The coefficient of the kinetic friction between block and floor (μk) is 0.5. What is the displacement of an object (s)? Acceleration due to gravity is 10 m/s2.
Known :
The coefficient of the kinetic friction (μk) = 0.5
Mass of block (m) = 4 kg
Acceleration due to gravity (g) is 10 m/s2
Temperature and heat – problems and solutions
1. On a thermometer X, the freezing point of water at -30o and the boiling point of water at 90o. 60OX = ….. oC.
Known :
The freezing point of water = -30o
The boiling point of water = 90o
Wanted : 60oX = ….. oC
Solution :
Thermodynamics – problems and solutions
The first law of thermodynamics
1. Based on graph P-V below, what is the ratio of the work done by the gas in the process I, to the work done by the gas in the process II?
Known :
Process 1 :
Pressure (P) = 20 N/m2
Initial volume (V1) = 10 liter = 10 dm3 = 10 x 10-3 m3
Collisions – problems and solutions
1. Object A (3 kg) moves at a speed of 8 m/s and object B (5 kg) moves at a speed of 4 m/s. If the collision between the object A and B is perfectly elastic, what is the velocity of object A and B after the collision?
Known :
Mass of object A (m1) = 3 kg
Mass of object B (m2) = 5 kg
The speed of object A (v1) = 8 ms–1
The speed of object B (v2) = 4 ms–1
