Given below are a few situations. Study them and state in which of the given cases work is said to be done. Give reasons for your answer. A bullock pulling cart upto 1 km on road.

In only one of the circuits given below, the lamp L lights. Which circuit is it? Given reason for your answer.

State which of the following are equations(with a variable).Give reason for your answer.Identify the variable from the equations with a variable. 2n + 1 = 11

State if each of the following statements is true or false. Give reasons for your answer:- Work done in the motion of a body over a closed loop is zero for every force in nature.

Given below are some functions of x and t to represent the displacement of an elastic wave. y=100cos(100pit+0.5x) State which of these represent a travelling wave along -x direction a stationary wave beats a travelling wave along +_(x) directions. Given reason for your answers.

State which of the following events are independent. Give reasons for your answer: E_1 : 'an even number on first throw' E_2 : 'a number multiple of 3 on second throw' in two successive throws of a dice.

State which of the following events are independent. Give reasons for your answer: E_1 : 'a total of 9 on first throw' E_2 : 'a total of 9 on second throw' in two successive throws of a pair of dice.

Given below are some functions of x and t to represent the displacement of an elastic wave. y= 5 cos (4x) sin (20t) State which of these represent (a) a travelling wave along (−x) direction (b) a stationary wave (c) beats (c) a travelling wave along (+x) direction. Give reasons for the answers.