hello:) I don’t really understand this graph. I thought uniform acceleration means the velocity is constant so it’s a constant gradient?

Uniform acceleration means that the object is accelerating at a constant rate. Since there is still acceleration, velocity is not constant. In fact, the velocity is increasing. This means that the object is moving faster and faster at a constant rate.

This graph is a displacement-time graph so its gradient would represent the velocity of the object. The velocity increases hence the gradient should increase (which means that the graph must be steeper and steeper with increasing time).

Constant gradient of a displacement-time graph would mean that there is no acceleration since gradient of the graph does not change so velocity is constant.

Note that it is the rate of change of velocity that is constant during uniform acceleration, not velocity.

- measure reactants precisely. ( first choice)

- stir to the reaction take place. ( second choice)

- wait patiently until the reaction completes. ( fourth choice)

- make sure to recover as much copper as possible. ( last choice)

+15-35=-20

going in opposite directions