SINDH MDCAT 2014 PAPER

1. A sound wave with a frequency of 343 Hz travels through the air. What is its wavelength? (speed of sound through air = 343 m/s)

2. When a force acts at right angles to the displacement 10 = 90`) the work is zero i.e.. the force does not produce work. Identify the example/s from the following when work is zero:

I. it is considered “hard work” to hold a heavy stone stationary at stretched hand

II. a person walks along a level surface while carrying a box

III. when a body moves in circular path

3. A neutron travels a distance of 12 m in a time interval of 3.6 x 10^4 s. Assuming its speed was constant, its kinetic energy is: (take I.7x 10^27 kg as the mass of neutron)

4. A student is performing a lab experiment on simple harmonic motion. He has two different springs (with force constants k1 and k2 ) and two different blocks (of masses m1 and m2). If K1 = 2k2, and m1 = 2m2, which of the following combinations would give the student the spring-block simple harmonic oscillator with the shortest period

5. A microscope has an objective of 10 mm focal length and eye piece of 25 mm focal length. What is the distance between the lenses, if the object is in sharp focus when It is 10.5 mm from the objectives

6. Light can he polarized by which of the following method/s:

I. scattering of light

II. double refraction

Ill. reflection

7. A steel rod has a length of 15 m at a temperature of 30 C. If the temperature is raised to 45°C. The increase in its length is: α =1.1×10-^5 k-^1

8. The volume occupied by a gram mole of a gas at 0 C and a pressure of 1 atmosphere is:

9. In the circuit shown below, 4 amperes is the current through R1. The potential difference across R1 in volts is:

10. Germanium and silicon are semiconductors having crystalline structures. Both these materials have _____ valence electrons in their outer most shells.