4. suppose the pendulum of a grandfather clock expands because of heat. will it overcount or undercount time?

under count

Explanation:

Time period of simple pendulum clock is given by

where L=length of pendulum

g=acceleration due to gravity

With increase in temperature there is increase in length as material expands with increasing temperature

and time period is inversely proportional to the square root of length therefore time period decreases and it under counts time  

  distance on the y-axis and time on the x-axis.

explanation:

the instantaneous velocity = change in position/time taken

the slope of the graph should give instantaneous velocity.

  slope of a graph = change in value of y -axis / change in values of x -axis

  comparing both the equations

    change in value of y -axis = change in position

  change in values of x -axis = time taken

so position values should be on the y axis and time values should be on the x axis.

distance on the y-axis and time on the x-axis.