A compressor
A refrigerator
Air blower
Air conditioner
Correct answer is D
Compressor is an instrument to supply air or other gas at increased pressure
Refrigerator is an appliance to keep things cold
Air blower is used to release air
Air conditioner is used to remove heat and maintain a stable temperature in an occupied space
Three 3ω resistance are connected in parallel what is the equivalent resistance?
1ω
9ω
3ω
0.33ω
Correct answer is A
Resistor connected in a parallel have an equivalence given by
\(\frac{1}{\text{Reff}}\) = \(\frac{1}{3}\) + \(\frac{1}{3}\) + \(\frac{1}{3}\)
= \(\frac{1 + 1 + 1}{3}\) = \(\frac{3}{3}\) = 1
Reff = 1ω
80.0%
76.6%
66.7%
60.7%
Correct answer is C
Efficiency = \(\frac{ma}{V.R}\) x \(\frac{100}{1}\)
V.R = number of pulleys = 6
ma = \(\frac{\text{Load}}{\text{Effort}}\) = \(\frac{200}{50}\) = 4
Efficiency = \(\frac{4}{6}\) × 100 = 66.67%
Which of the following statements is NOT correct?
Molecules of a liquid are stationary
Brownian motion is an evidence of particle nature of matter
Matter is made up of molecules
The molecules of matter are in constant motion
Correct answer is A
Molecules of liquid are not stationary
Brownian motion is an evidence of particle nature of matter
matter is made up of molecules
The molecules of matter are in constant motion
A cell of internal resistance 2 π supplies current to a 6 π resistor. The efficiency of the cell is
12.0%
25.0%
33.3%
75.0%
Correct answer is C
Internal resistance determine the maximum current that can be supplied
Efficiency = \(\frac{r}{R}\) × 100
= \(\frac{2}{6}\) × 100
= 33.3%