Prelims

Which one of the following is the correct sequence in increasing order of molecular weights of the hydrocarbons ?

Which one of the following is NOT radioactive ?

Which of the following distance-time graph (x – t) represents one-dimensinal uniform motion?

Assertion (A): A Chemical reaction becomes faster at higher temperatures. Reason (R): At higher temperatures, molecular motion becomes more rapid.

The following table shows the percentage change in the consumption of electricity by five towns P, Q, R, S, T from 1986 to 1988 .If town T consumed 500,000 units in 1986, how much did it consume in 1988 ?

A radioactive substance has a half-life of four months. Three-fourth of the substance would decay in

Which of the following weather conditions is indicated by a sudden fall in barometer reading ?

Consider the following statements : A simple pendulum is set into oscillation. Then I. the acceleration is zero when the bob passes through the mean position. II. in each cycle the bob attains a given velocity twice. III. both acceleration and velocity of the bob are zero when it reaches its extreme position during its oscillation. IV. the amplitude of oscillation of the simple pendulum decreases with time. Which of these statements are correct ?

Cloudy nights are warmer compared to clear cloudless nights, because clouds

The mass of a body on Earth is 100 kg (acceleration due to gravity, ge – 10 m/s2). If acceleration due to gravity on the Moon ge/6, then the mass of the body on the moon is