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Free International Baccalaureate Diploma Programme Exam Style Questions
Discover our free International Baccalaureate Physics past paper questions and put your knowledge to the test. Engage with a variety of questions covering Physics topics to enhance your understanding and excel in your IB Physics exams.
Question 1
The acceleration of free fall g is determined by the relationship $g = \frac{4\pi ^2 l}{t^2}$. The uncertainty in the value of $g$ is 20% and the uncertainty in the value of $l$ is 6%. What is the uncertainty in $t$?
[ 1 ]
A.
7%
B.
9%
C.
13%
D.
15%
Rationale
When calculating uncertainties, a distinction must be made between what is measured and what is calculated. The calculated should be made the subject of the formula before proceeding.
$$t = \sqrt{\frac{4\pi l}{g} }$$
$$\frac{\Delta t}{t}=\frac{1}{2} \frac{\Delta l}{l} + \frac{1}{2} \frac{\Delta g}{g} $$
$$= 3\% + 10\% = 13\%$$
Question 2
A scooter is moving on a zigzag road. What is this an example of?
[ 1 ]
A.
Point object
B.
1-Dimensional motion
C.
2-Dimensional motion
D.
3-Dimensional motion
Rationale
The scooter is moving in the x and y plane!
Question 3
How many fundamental quantities exist in physics?
[ 1 ]
A.
10
B.
3
C.
7
D.
Infinite
Rationale
Mass, Length, Time, Electric Current, Amount of substance, Temperature and Luminous intensity are the 7 fundamental quantities in physics.
Question 4
A truck breaks down on the road. It has been resting on a rough horizontal plane, and a mechanic calculates that the truck will require a pull of 150 N inclined at 30° to the plane just to move it using a pulling truck. On a data sheet it was collected that a push of 200 N inclined at 30° to the plane just moved the body. Estimate the weight of the truck in N.
[ 1 ]
A.
70.71 N
B.
599.88 N
C.
1697.22 N
D.
494.97 N
Rationale
Given: $\theta = 30 ^ { \circ }$
Let $\mathrm { W } =$ Weight of the body in newtons,
$R _ { N } =$ Normal reaction,
$\mu =$ Coefficient of friction, and
$\mathrm { F } =$ Force of friction.
First of all, let us consider a pull of $150 \mathrm {~N}$. The force of friction (F)
acts towards left
Resolving the forces horizontally,
$F = 150 \cos 30 ^ { \circ } = 129.90 \mathrm {~N}$
Now resolving the forces vertically,
$R _ { N } = W - 150 \sin30 ^ { \circ } = ( W - 75 ) N$
We know that $F = \mu \cdot R _ { N } \quad$ or $\quad 129.90 = \mu ( W - 75 ) \quad \ldots$ (i)
Now let us consider a push of $200 \mathrm {~N}$. The force of friction (F) acts
towards right.
Resolving the forces horizontally,
$F = 200 \cos 30 ^ { \circ } = 173.21 \mathrm {~N}$
Now resolving the forces vertically,
$R _ { N } = W + 200 \sin 30 ^ { \circ } = ( W + 100) N$
We know that $\quad F = \mu \cdot R _ { N } \quad$ or $\quad 173.21 = \mu ( W + 100 ) \quad \ldots$ (ii)
From equations (i) and (ii),
$W = 599.88$, and $\mu = 0.2475$
Question 5
Estimate the ratio between the mass of the sun and the mass of a person to the closest order of magnitude?
[ 1 ]
A.
$10^{100}$
B.
$10^4$
C.
$10^{72}$
D.
$10^{28}$
Rationale
Mass of the sun is $10^{30}$ kg
Average human weighs around $10^2$ kg
Question 6
Two lengths, $a$ and $b$, are measured to be $51 \pm 1{\text{ cm}}$ and $49 \pm 1{\text{ cm}}$ respectively. Calculate the absolute uncertainty when the following calculation is performed.
$\frac{a}{b}$
[ 1 ]
A.
1 cm
B.
100 cm
C.
0.5 cm
D.
50 cm
Rationale
Propagation of uncertainties for multiplication and division follows the sum of the fractional uncertainty multiplied by the combined calculated value.
$\frac{1}{51}$ + $\frac{1}{49}$ = $\frac{\Delta x}{2499}$
$\Delta x$ = 100 cm
Question 7
An IB physics student conducts an experiment to measure the average velocity of a trolley using two light gates placed at a distance of 100 cm between each other. The table below shows the data collected by the student.
| Trial 1 | Trial 2 | Trial 3 | Trial 4 | Trial 5 | |
|---|---|---|---|---|---|
| Time taken for the trolley to cover 100 cm in seconds | 10.1 | 10.3 | 9.8 | 9.6 | 10.5 |
[ 1 ]
From the data table, calculate the uncertainty of the trials taken by the student, in two decimal places?
A.
0.90
B.
0.10
C.
0.45
D.
0.05
Rationale
The uncertainty of multiple trials is equal to:
$\frac{Range}{2}$
Question 8
An IB physics student conducts an experiment to measure the spring constant of helical spring. The student measures the extension of the spring for an attached weight of 1kN. The table below shows the data collected by the student.
| Trial 1 | Trial 2 | Trial 3 | Trial 4 | Trial 5 | |
|---|---|---|---|---|---|
| Extension of the spring in mm | 11.85 | 13.11 | 9.10 | 9.10 | 12.02 |
[ 1 ]
An analog scale was used to measure the extension of the spring. What is the uncertainty of the trials in the collected data table, in 2 significant figures?
A.
2.0 mm
B.
0.01 mm
C.
0.10 mm
D.
4.0 mm
Rationale
The uncertainty of multiple trials is equal to:
$\frac{Range}{2}$
Question NaN
The acceleration of free fall g is determined by the relationship $g = \frac{4\pi ^2 l}{t^2}$. The uncertainty in the value of $g$ is 20% and the uncertainty in the value of $l$ is 6%. What is the uncertainty in $t$?
[ 1 ]
A.
7%
B.
9%
C.
13%
D.
15%
Rationale
When calculating uncertainties, a distinction must be made between what is measured and what is calculated. The calculated should be made the subject of the formula before proceeding.
$$t = \sqrt{\frac{4\pi l}{g} }$$
$$\frac{\Delta t}{t}=\frac{1}{2} \frac{\Delta l}{l} + \frac{1}{2} \frac{\Delta g}{g} $$
$$= 3\% + 10\% = 13\%$$
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