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.
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.