Which of the following simple machines is a second class lever?
wheel barrow
crowbar
claw hammer
seesae
Correct answer is A
No explanation has been provided for this answer.
0.09
0.18
0.36
0.54
Correct answer is B
a = \(\frac{v^2 + u^2}{2s} = \frac{0^2 + 3^2}{2 \times 2.5}\) = 1.8m/s2
F = ma = 25 x 1.8 = 45N
N = mg = 25 x 10 = 250
but \(\mu = \frac{F}{R} = \frac{45}{25 \times 10} = 0.18\)
The friction which exists between two layers of liquid in relative motion is called
capillarity
surface tension
viscosity
cohesion
Correct answer is C
No explanation has been provided for this answer.
Which of the following statements about a spring balance and/or a chemical balance is not correct?
the chemical balance operates on the principle of moments
the spring balance operates on Hooke's law
either may be used to measure the weight of a substance
the reading of a spring balance changes over the surface of the earth, while that of the chemical balance remains constant
Correct answer is C
No explanation has been provided for this answer.
electric potential (Vector)
momentum (scalar)
gravitational field intensity (scalar)
magnetic flux density (vector)
Correct answer is D
No explanation has been provided for this answer.