Physics GRE Subject Practice Test MCQs Questions

GRE Tests

1) If the speed of particle is doubled then its kinetic energy becomes
(a) Doubled.
(b) Unchanged
(c) Four time.
(d) Half of the initial value

2) A ping – pong ball of mass m moving with velocity v bounces off a concrete surface with the same speed in the opposite direction. The change in it’s linear momentum is
(a) 2mw
(b) mv
(c) 1/2mv
(d) Zero

3) The work done by a force of 20 N in displacing an object through a distance of 5 cm is
(a) 100 J
(b) 4 J
(c) 400 J
(d) 1 J

4) The weight of an astronaut in space far from any planet in
(a) Zero
(b) Different than on earth
(c) Same on earth

5) A net force needed to give a mass of 250 kg an acceleration of 5 cm/sec2 is
(a) 25N
(b) 12.5N
(c) 10N
(d) 5N

6) A light year is a unit of
(a) Time
(b) Distance
(c) Velocity
(d) Intensity of light

7) A spaceship is circling a planet at a distance of 10000 km from its center. Assume that the radius of the planet is 5000 km mid the acceleration clue to gravity on it’s surface is 10 rn/sec2. The speed of the spaceship is
(a) 5 km/sec
(b) 1 km/sec
(c) 10km/sec
(d) 25 km/sec

8) A uniform spring with force constant K is cut into halves. Whet is the spring constant for one of the halves?
(a) Half of the original one.
(b) Twice the original one
(c) 1/4 of original one
(d) Same original one

9) A watt is the unit of
(a) Energy
(b) Power
(c) Work
(d) Capacity

10) Two bodies are in thermal equilibrium with each other if they have same
(a) Pressure
(b) Density
(c) Energy
(d) Temperature

(11) The capacitive reactance of a 5-m F capacitor in a 20-kHz circuit is
(a) 0.63W
(b) 1.6W
(c) 5W
(d) 16W
(e) none of these

(12) The impedance of a circuit does not depend on
(a) I
(b) f
(c) R
(d) C
(e) all of these

(13) At resonance, itis not true that
(a) R=Z
(b) XL=1/XC
(c) P=IV
(d) I=V/R

(14) A voltmeter across an AC circuit reads 50 V and an ammeter in series with the circuit reads 5 A. The power consumption of the circuit
(a) is less than or equal to 250 W
(b) is exactly equal to 250 W
(c) is equal to or more than 250 W
(d) may be less than, equal to, or more than 250 W
(e) none of these

(15) The magnetic flux through a wire loop in a magnetic field B does not depend on
(a) the area of the loop
(b) the shape of the loop
(c) the angle between the plane of the loop and the direction of B
(d) the magnitude B of the field
(e) none of these

(16 The alternating current in the secondary coil of a transformer is induced by
(a) a varying electric field
(b) a varying magnetic field
(c) the iron core of the transformer
(d) motion of the primary coil
(e) none of these

(17) When a diamagnetic substance is inserted in a current carrying solenoid, the magnetic field is
(a) slightly decreased
(b) greatly decreased
(c) slightly increased
(d) greatly increased
(e) none of these

(18) The N-type semiconductor is electrically
(a) negative
(b) positive
(c) neutral
(d) charged

(19) When a 100¾ W, 240-V light bulb is operated at 200 V, the current that flows in it is
(a) 0.35 A
(b) 0.42 A
(c) 0.50 A
(d) 0.58 A
(e) none of these

(20) The a of a transistor is
(a) current gain in common base
(b) current gain in common emitter
(c) voltage gain in common emitter
(d) voltage gain in common base
(e) none of these