Physics Past Questions and Answers

A weight of 1000 grams hangs from a lever 20cm to the fulcrum. At the left is a 500-gram weight 20cm from the fulcrum, and a 200-gram weight x cm away from the fulcrum. What is the value of x that will make the lever balanced?

A 50cm
B 20cm
C 10cm
D 30cm
E 70cm

Question 37:

Radio carrier waves are generated by causing electrons to oscillate rapidly in

A A microphone
B A television camera
C An antenna
D Coaxial cables
E A transmitter

Question 38:

Which of the following statements is correct? Silvered walls of a vacuum flask are used to prevent

A Heat loss due to conduction
B Vacuum loss
C Heat entry into the inner flask due to convection
D Heat loss due to radiation
E Heat loss due to convection

Question 39:

A concave lens of focal length 20cm form an image 1/2 the size of the object. The object distance is

A 100cm
B \( \frac{100}{q} \)
C 60cm
D \( \frac{60}{7} \)
E None of the above

Question 40:

The diagram shows lens arrangement in

A A Compound Microscope
B Astronomical telescope
C Binocular
D Periscope
E Projection lantern