A small ball is dropped from a height of 2 m and bounces a few times after landing on a cement floor - NSC Physical Sciences - Question 3 - 2020 - Paper 1
Question 3
A small ball is dropped from a height of 2 m and bounces a few times after landing on a cement floor. Ignore air friction.
The position-time graph below, not drawn ... show full transcript
Worked Solution & Example Answer:A small ball is dropped from a height of 2 m and bounces a few times after landing on a cement floor - NSC Physical Sciences - Question 3 - 2020 - Paper 1
Step 1
Define the term free fall.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Free fall is a condition in which an object is falling solely under the influence of gravity, with no other forces acting upon it, such as air resistance.
Step 2
3.2.1 The time that the ball is in contact with the floor before the first bounce
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
From the graph, the ball is in contact with the floor from time 0 seconds to approximately 0.64 seconds. Hence, the time of contact is 0.64 seconds.
Step 3
3.2.2 The time it takes the ball to reach its maximum height after the first bounce
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The time of the first bounce can be determined from the graph. It appears the ball reaches its maximum height approximately at 1.07 seconds (0.64 s + 0.43 s for ascent) after the first impact.
Step 4
3.2.3 The speed at which the ball leaves the floor after the first bounce
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To calculate the speed as the ball leaves the floor, we can use the equation for free fall:
v = rac{y_f - y_i}{t}
Here, yf is the maximum height (approx. 1.8 m), yi is the lowest position (0 m), and t is the time (0.43 seconds). Hence,
v = rac{1.8 ext{ m} - 0 ext{ m}}{0.43 ext{ s}}
Calculating the above gives a speed of approximately 4.19 m/s.
Step 5
3.2.4 Time indicated on the graph
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The total time indicated on the graph for the motion of the ball is approximately 2.97 seconds, as noted from the x-axis of the graph.