A beam of radiation is passed between a pair of charged plates as indicated in the fig above. Beam P is undetected While Q is deflected to the left. P and Q respectively should be
I.γ-rays β-rays
II. x-rays β-rays
III. γ-rays x-rays
IV. x-rays x-rays
- A. I only
- B. III only
- C. I and II
- D. III and IV
The fig above shows a conductor PQ carrying a current I in the direction shown. At a particular position near the conductor is a compass needle K. Neglecting the earth’s magnetic field, the compass needle will
- A. settle in any direction
- B. settle in a fixed direction only if the conductor PQ is a magnetic material
- C. settle in a fixed direction WHETHER the conductor PQ is a magnetic material OR NOT
- D. be stationary
The total power drawn from the cell in the circuit above is
- A. 12W
- B. 24W
- C. 32W
- D. 40W
Three 2-µF capacitors are arranged as seen in the circuit above . The effective capacitance between E and F is
- A. 0.75µF
- B. 1.33µF
- C. 3.00µF
- D. 6.00µF
In the above circuit diagrams A is the ammeter and V is the Voltmeter. Which of the circuits is correct for finding the correct value of the resistance R
- A. I
- B. II
- C. III
- D. IV
The air column as shown above is set into vibration by the turning fork. In this State of resonance, the waves in the air column will be
- A. stationary and transverse
- B. stationary and longitudinal
- C. progressive and transverse
- D. progressive and longitudinal
In the fig above W1 = 200g, and W2 =450g . Calculate the extension of the spring per unit load?
[g = 10ms-2]
- A. 6.0 x 10-5mN-1
- B. 2.5 x 10-4mN-1
- C. 6.0 x 10 -3mN-1
- D. 2.5 x 10 -2mN-1
A block of mass m is held in equilibrium against a vertical wall by a horizontal force. If the coefficient of friction between the wall and the block is µ, the minimum value of the horizontal force is
- A. µmg
- B. (1-µ)mg
- C. (1+µ)mg
- D. mg/µ
A simple pendulum of mass m moves along an arc pf a circle radius R in a vertical plane as shown above. What is the work done by gravity in a downward swing through the angle q to 0 degree
- A. mgR sinθ
- B. MgR (1- cos θ)
- C. mgR
- D. mgR (1 - sinθ)
The fig above shows a uniform circular object, center R and diameter PS. A circular section 6 and Diameter PR is cut from it. if PQRS is a straight line, where is center of gravity of the figure
- A. Q
- B. R
- C. A point between P and R
- D. A point between R and S
The function of a 5-A fuse included in a circuit supplying a household refrigerator with power is to keep the
- A. Temperature of the refrigerator low and constant
- B. keep current supplied to the refrigerator below 5A
- C. Voltage supply constant
- D. Current supplies to the refrigeration
An object is placed at 5.6 x 10-4m in front of a converging lens of focal length 1.0 x 10-nm. The image formed is
- A. Real, Erect and magnified
- B. Virtual, erect and magnified
- C. Real, inverted and magnified
- D. Virtual, erect and diminished
Eight alpha decays and six beta decays are necessary before an atom of 2 \(^{238}_{92}U\) achieves stability. The final product in the chain has an atomic number of
- A. 70
- B. 78
- C. 82
- D. 90
Which of the following is TRUE of the particles emitted in radioactive disintegration?
- A. the beta particle is the helium nucleus H
- B. the alpha particle is lighter than the beta particle
- C. the alpha particle is deflected more than the beta particle in a magnetic field
- D. the beta particle is deflected more than the alpha particle in a magnetic field
When a radiation strikes a metal surface, electrons may be ejected from the metal. The maximum kinetic energy which may be acquired by an ejected electron depend on the
- A. intensity of the radiation
- B. source of the radiation
- C. wavelength of the radiation
- D. detection device of the electron
The electrochemical equivalent of silver is 0.0012gC-1. If 36.0g of silver is to be deposited by electrolysis on a surface by passing a steady current for 5.0mins, the current must be
- A. 6000A
- B. 100A
- C. 10A
- D. 1A
An ammeter of resistance 1.0\(\Omega\) has a full-scale deflection of 50mA. Determine the resultant full-scale deflection of the meter when a shunt of 0.0111\(\Omega\) is connected across its terminals.
- A. 400mA
- B. 450mA
- C. 500mA
- D. 550mA
A calibrated potentiometer is used to measure the e.m.f. of a cell because the
- A. internal resistance of a cell is small compared with that of the potentiometer
- B. potentiometer has a linear scale
- C. potentiometer takes no current from the cell
- D. resistance of the potentiometer is less than that of a voltmeter
Three resistors, with substances 250\(\Omega\), 500\(\Omega\) and 1k\(\Omega\) are connected in series. A 6V battery is connected to either end of the combination. Calculate the pot3ential difference between the end of the 250\(\Omega\) resistor.
- A. 0.20V
- B. 0.86V
- C. 1.71V
- D. 3.43V
The resistance of a 5m uniform wire of cross-sectional area 0.2 x 10-6m2 is 0.425. What is the resistivity of the material of the wire?
- A. 1.10 x 10-6\(\Omega\)m
- B. 4.25 x 10-6\(\Omega\)m
- C. 2.40 x 10-7\(\Omega\)m
- D. 1.70 x 10-8\(\Omega\)m
A bar magnet is most effectively demagnetized by
- A. placing it in a N - S position and hitting it with a hammer
- B. subjecting it to an electric current from a battery
- C. bringing its north pole in contact with the north pole of a very strong magnet
- D. heating the magnet