Question 41Which type of mirrors are capable of producing parallel beams of light such as those arising from the headlamps of a car? A. Cylindrical mirrorsB. Parabolic mirrorsC. Spherical mirrorsD. Plane mirrors Objective Show full explanation
Question 42A person can focus an object only when it lies within 200cm from him. Which spectacles should be used to increase his maximum distance of distinct vision to infinityA. Concave lensB. Plane glassesC. BinocularsD. Convex lensObjective Show full explanation
Question 43Calculate the angle of minimum deviation for a ray which is refracted through an equiangular prism of refractive index 1.4 A. 29°B. 60°C. 99°D. 90°Objective Show full explanation
Question 44As the pressure of a fluid increases, its viscosityA. DecreasesB. Remains constantC. Increases then decreases D. Increases Objective Show full explanation
Question 45In a hydraulic press, a force of 40N is applied on the effort piston of area 0.4m2. If the force exerted on the load piston is 400N, the area of the large piston is A. 8m2B. 4m2C.2m2D. 1m2Objective Show full explanation
Question 46The earth is four times the size of the moon and the acceleration due to gravity on the earth is 80 times that on the moon. The ratio of the mass of the moon to that of the earth is A. 1:320B. 1:1280C. 1:80D. 1:4Objective Show full explanation
Question 47A moving coil galvanometer has a full scale deflection of 3A equivalent to 30° deflection. The sensitivity of the instrument is A. 10.0B. 33.0C. 90.0D. 0.1Objective Show full explanation
Question 48An a.c circuit of e.m.f 12V has a resistor of resistance 8Ω connected in series to an inductor of inductive reactance 16Ω and a capacitor of capacitive reactance 10Ω. The current flowing in the circuit is A. 1.4AB. 14.0AC. 1.2AD. 12.0AObjective Show full explanation
Question 49When left in a freezer, a bottle full of water cracks on freezing into ice because of the A. Decrease in volume of waterB. Contraction of the bottle C. Expansion of the bottle D. Increase in the volume of water Objective Show full explanation
Question 50The difference between X-rays and Gamma rays is that A. X-rays arise from energy changes in the electronic structure of atoms while gamma rays come from the nucleusB. X-rays are electromagnetic radiations while gamma rays are negatively charged radiations C. X-rays have higher frequencies then gamma raysD. X-rays are more penetrating than gamma rays Objective Show full explanation