A deep-sea research submersible descends along a vertical guide cable. Its depth profile is plotted on the distance-time graph below.
a.[2]
Some physical quantities are scalars and others are vectors.
Which of the following are vector quantities? Select two:
- Speed
- Mass
- Displacement
- Distance
- Velocity
b.[1]
What was the total distance travelled by the submersible in 1500 seconds1500\text{ seconds}1500 seconds?
c.[2]
Calculate the average speed of the submersible during the entire 1500 seconds1500\text{ seconds}1500 seconds.
d.[2]
Which section of the graph (A, B, or C) represents the submersible descending the slowest? Give a reason for your answer.
e.[1]
Complete the following sentence:
When returning to the surface, the motors of the submersible do work against the downward force of ____________.