Additional Answer Options: 3.2

3.1

Downwards.

The only force acting on the object is the gravitational force which acts downwards.

Or

The only force acting is gravitational force.

Or

Gravitational force acts downwards.

Or

The ball is in free fall.

Or

(Gravitational) acceleration is downwards.

Tip: when an object is in free fall, regardless of whether it is moving upward or downward in motion, the only force acting on the object is the gravitational force which acts downwards.

2 marks

(2 x 1 mark)

3.2

Option 1

Upwards as positive

Or

Downwards as positive

Tips:

• The velocity of the ball at the highest point in its motion, when it is thrown upwards is always zero.
• Remember, that all velocities as well as accelerations are vector quantities and, therefore, require directions.

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3 marks

(3 x 1 mark)

3.3

Option 1

Upwards as positive

At the highest point v_f is zero:

This is higher than the height needed to reach point T (2,1 m) therefore the ball will pass point T.

Or

Downwards as positive

At the highest point v_f is zero:

This is higher than the height needed to reach point T (2,1 m) therefore the ball will pass point T.

There are more ways to answer this question. To view other options, click here.

5 marks

(5 x 1 mark)

Marking criteria:

• Formula mark
• Substitution mark
• Mark for height/distance
• Mark for comparison
• Mark for conclusion

3.4

Tips: 

• When bulleted things are listed to be indicated on a graph, these must be shown as this is usually how the marks are allocated, and if any of the requirements are left out, you will lose marks.
• Since the motion is free fall, the gradient of the line will be constant and equal to 9,8 m·s^-2.

2 marks

(2 x 1 mark)

Marking criteria:

• Initial velocity and time for final velocity are shown 
• Correct straight line (including orientation) drawn