PF Unit 3 Test 1

On a curved xt graph the slope of the secant represents what?

• average acceleration

• distance

• instantaneous velocity

• instant acceleration

What is the shape of an xt graph that shows an object moving with a changing speed?

• circular

• straight and flat

• vertical

• curved

Which graph shows and object speeding up in the negative direction?

• Graph

  A

• Graph B

• Neither graph

• It is impossible to tell without a v-t graph

Which graph shows an object moving at a constant speed in the positive direction.

• Graph

  A

• Graph B

• Neither graph

• It is impossible to tell without a v-t graph.

Which of the following is NOT part of a non-constant speed word description

• Where the object starts

• if it is speeding up or slowing down

• if it is going fast or slow

• the direction it moves in

Choose the part of the word description that is correct.

• starts at zero

• moves in the negative direction

• speeds up then slows down

• slows down then speeds up

Which of the following pair of time intervals could be used to find the instantaneous velocity at 0.2s.

• 0.0 and 0.6s

• 0.1 and 0.3s

• 0.1 and 0.5s

• 0.2 and 0.4s

A curved line on an x-t graph

• does not show direction

• does not show position

• cannot be used to calculate slope from start to finish

• does not show where fast and slow speed occur .

(Ignore the red arrows) Which choice describes where the object is speeding up on the motion diagram?

• Where it starts at zero.

• in the negative direction

• In the positive direction between stops

• It is never speeding up.

Define secant

• a straight line drawn inside of a curve on a graph

• a unit of time

• a straight line drawn outside of a curve on a graph

• another name for a vt graph