Ashley

Physics

12 March, 15:01

1. A speed-time graph shows that a car moves at 20 m/s for 15 s. The car's speed then steadily decreases until it comes to a stop at 40 s. Which of the following describes the slope of the speed-time graph from 15 s to 40 s?

A. linear, sloping downward

B. linear, sloping upward

C. linear, horizontal

D. curved, upward

2. A river current has a velocity of 10 km/h relative to the shore, and a boat moves in the same direction as the current at 10 km/h relative to the river. How can the velocity of the boat relative to the shore be calculated?

A. by dividing the river current vector by the boat's velocity vector

B. by multiplying the vectors

C. by adding the vectors

D. by subtracting the river current vector from the boat's velocity vector