Agrandfather clock is "losing" time because its pendulum moves too slowly. assume that the pendulum is a massive bob at the end of a string. a grandfather clock is "losing" time because its pendulum moves too slowly. assume that the pendulum is a massive bob at the end of a string. the motion of this pendulum can be sped up by: a. shortening the string. b. lengthening the string. c. increasing the mass of the bob. d. decreasing the mass of the bob.

a. shortening the string.

Explanation:

Time period of a pendulum is given by

where,

L =  Length of pendulum

g = Acceleration due to gravity = 9.81 m/s²

Here, the pendulum is slowing down this means that the time period is increasing. As the time period is proportional to the length it implies that the length of the pendulum is increasing.

Hence, in order to make the pendulum speed up or reduce the time period the length of the pendulum needs to be shortened.

answer///isobars;