physics

The energy required to separate the nucleus in an atom completely is known as?

A. mass defect of the atom B. electron binding energy C. excitation energy D. nuclear bonding energy Correct Answer: Option…

6 years ago

The circuit below illustrates a standard resistor R, voltage source E and a lamp L connected in series. If the temperature of R is increased, the brightness of the lamp will?

A. increase sharply B. decrease slightly C. remains the same D. increase gradually Correct Answer: Option B B. decrease slightly

6 years ago

A transformer has 400 turns of wire in the primary coil and 40 turns in the secondary coil. If the input voltage is 150 volts. Calculate the magnitude of the output voltage

A. 150V B. 55V C. 36V D. 15V Correct Answer: Option D D. 15V Explanation ES/EP=Ns/Np=Es/150=40/400 Es = (150×40)/400 =…

6 years ago

A wire of length 100 cm has a resistance of 10Ω. If its cross-sectional area is 0.005cm², determine its resistivity.

A. 0.0005Ωcm B. 0.0015Ωcm C. 0.0016Ωcm D. 0.0700Ωcm Correct Answer: Option A A. 0.0005Ωcm Explanation e = R/AL=(10×0.005)/100=0.0005  

6 years ago

In the circuit diagram below, E is a battery of negligible internal resistance. If its emf is 9.0V. Calculate the current in the circuit

A. 1.8A B. 1.0A C. 0.8A D. 0.3A Correct Answer: Option B B. 1.0A Explanation 1/r=1/r1+1/r2 = 1/5+1/20 = (4+1)/20=5/20…

6 years ago

A 15μF capacitor is connected to a 240V, 50Hz ac. source. Calculate the reactance of the capacitance [π=3.142]

A. 16Ω B. 68Ω C. 106Ω D. 212Ω Correct Answer: Option D D. 212Ω Explanation Xc=1/2πFc = 2 x 3.142…

6 years ago

An electric motor converts?

A. electrical energy to mechanical energy B. mechanical energy to electrical energy C. mechanical energy to chemical energy D. electrical…

6 years ago

Which of the following conditions occur at resonance in a series RLC circuit?

i. Impedance equal resistance ii. Current is maximum iii. Reactance is maximum iv. Current and voltage are 90o out of…

6 years ago

The energy stored in a simple cell is?

A. electrical B. nuclear C. thermal D. chemical Correct Answer: Option D D. chemical

6 years ago