GS One‑Liners
high‑yield facts · smart revision
5107
facts
5107
results
Latest facts first
| # | Question & Answer |
|---|---|
| 4201 |
Can potential energy be converted into kinetic energy in machines?
-
Yes, as in a falling weight or swinging pendulum
|
| 4202 |
What is the principle of conservation of energy in machines?
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Energy input equals useful energy output plus energy lost to friction or other factors
|
| 4203 |
What is the relationship between work input, work output, and efficiency?
-
Efficiency = (Work output / Work input) × 100%
|
| 4204 |
What is work input and work output in a machine?
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Work input: effort × distance; Work output: load × distance moved by load
|
| 4205 |
Can energy be lost in machines?
-
Yes, due to friction, air resistance, or deformation
|
| 4206 |
How is mechanical advantage of a pulley system calculated?
-
MA = Load / Effort
|
| 4207 |
What is the difference between fixed and movable pulleys?
-
Fixed pulley changes direction; movable pulley reduces effort
|
| 4208 |
What is a pulley?
-
A wheel with a grooved rim used to change the direction of a force or lift loads
|
| 4209 |
How is mechanical advantage of an inclined plane calculated?
-
MA = Length of slope / Height of plane
|
| 4210 |
What is an inclined plane?
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A flat surface inclined at an angle to the horizontal, used to raise or lower loads
|
| 4211 |
How is mechanical advantage of a lever defined?
-
Ratio of load force to effort force
|
| 4212 |
What are the three types of levers?
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First-class, second-class, and third-class levers
|
| 4213 |
What is a lever?
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A rigid bar that rotates about a fulcrum to lift or move loads
|
| 4214 |
Name the types of simple machines.
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Lever, Inclined Plane, Pulley, Wheel and Axle, Screw, Wedge
|
| 4215 |
What is a simple machine?
-
A device that changes the magnitude or direction of a force to make work easier
|
| 4216 |
How is efficiency of a machine calculated?
-
Efficiency = (Useful work output / Total work input) × 100%
|
| 4217 |
What is the SI unit of power?
-
Watt (W)
|
| 4218 |
What is power?
-
Rate at which work is done, P = W/t
|
| 4219 |
Can mechanical energy be converted from one form to another?
-
Yes, between kinetic and potential energy
|
| 4220 |
What is the law of conservation of mechanical energy?
-
The total mechanical energy (KE + PE) of a body remains constant if only conservative forces act
|
| 4221 |
What is potential energy?
-
Energy possessed by a body due to its position or configuration, PE = mgh
|
| 4222 |
What is kinetic energy?
-
Energy possessed by a body due to its motion, KE = ½ mv²
|
| 4223 |
When is work said to be negative?
-
When the force and displacement are in opposite directions
|
| 4224 |
When is work said to be positive?
-
When the force and displacement are in the same direction
|
| 4225 |
What is the SI unit of work?
-
Joule (J)
|