What is the name of the model of the atom that describes electrons as orbiting the nucleus in specific energy levels?

• A. Bohr model
• B. Dalton model
• C. Rutherford model
• D. Thomson model

I. A liquid boils when its saturated vapour pressure is equal to the external pressure II. Dissolved substances in pure water lead to increase in the boiling point. III. When the external pressure is increased, the boiling point increases. IV. Dissolved substances in pure water decrease the boiling point. Which combination of the above are peculiarities of the boiling point of a liquid?

• A. I, II and III
• B. I, II, III and IV
• C. I, II and IV
• D. II, III and IV

A boy timed 30 oscillations of a certain pendulum thrice and obtained 1min. 10s, 1min. 12s and 1min. 7s respectively.The mean period of oscillation of the pendulum is

• A. 0.14s
• B. 0.43s
• C. 2.32s
• D. 6.97s

If the load at the end of a sonometer wire is immersed in a bucket of water, the original fundamental frequency of the wire could be restored by

• A. decrease the length of the wire
• B. increasing the length of the wire
• C. increasing the mass per unit length of the wire
• D. changing the temperature of the wire

Solid friction, like viscosity is

• A. independent of the surface area in contact
• B. independent of the relative motion between layers
• C. dependent on normal reaction
• D. in opposition to motion

An object is protected with a velocity of 100m^-1 at an angle of 60^o to the vertical. Calculate the time taken by the object to reach the highest point (Take g as 10ms^-2

• A. 5.0s
• B. 8.7s
• C. 10.0s
• D. 17.3s

In which of the following media is the speed of sound the least?

• A. Air
• B. Brass
• C. Water
• D. Wood

Calculate the total distance covered by a train before coming to rest if its initial speed is 30ms^-1 with a constant retardation of 0.1m^-2

• A. 5500m
• B. 4500m
• C. 4200m
• D. 3000m

(a) In his first attempt, a long jumper took off from the springboard with a speed of 8 ms\(^{-1}\) at 30° to the horizontal. He makes a second attempt with the same speed at 45° to the horizontal. Given that the expression for the horizontal range of a projectile is \(\frac{v^2 sin \theta}{g}\) where all the symbols have their usual meanings, show that he gains a distance of 0.8576 m in his second attempt.

(b)(i) State Hooke's law of elasticity.

(ii) Describe an experiment to verify Hooke's law.

(iii) State two precautions you would take if you were to perform this experiment in the laboratory.

(c) A spiral spring of natural length 20.00 cm has a scale pan hanging freely in its lower end. When an object of mass 40 g is placed in the pan, its length becomes 21.80 cm. When another object of mass 60g Is placed in the pan, the length becomes 22.05cm. Calculate the mass of the scale pan. [g = 10 ms\(^{-2}\)]

I. Melting

II. Boiling

III. Refraction

IV. Conduction

Which combination of the above is evident of the molecular nature of matter?

• A. II , III and IV only
• B. I ,II and IV only
• C. I , III and IV only
• D. I , II and III only