Motion and kinematics — WPH11 IAL Physics practice questions · Study-IAL

Subjects
Physics
WPH11
1.1

Motion and kinematics

WPH11Topic 1.14 questions

Uniformly accelerated motion, motion graphs, scalars and vectors, and projectile motion.

Specification points

Be able to use the equations for uniformly accelerated motion in one dimension: $v = u + at$ , $s = \frac{(u + v)t}{2}$ , ,

Next topic 1.2Forces, moments and equilibrium

2(u+v)t

s = ut + \frac{1}{2}at^2

v^2 = u^2 + 2as

Be able to draw and interpret displacement-time, velocity-time and acceleration-time graphs

Know the physical quantities derived from the slopes and areas of displacement-time, velocity-time and acceleration-time graphs, including cases of non-uniform acceleration, and understand how to use the quantities

Understand scalar and vector quantities and know examples of each type of quantity and recognise vector notation

Be able to resolve a vector into two components at right angles to each other by drawing and by calculation

Be able to find the resultant of two coplanar vectors at any angle to each other by drawing, and at right angles to each other by calculation

Understand how to make use of the independence of vertical and horizontal motion of a projectile moving freely under gravity

CORE PRACTICAL 1: Determine the acceleration of a freely-falling object

Stuck on something?

Get a plain-language explanation, a worked example and the usual mistake.

Questions

Multiple choice: 1
Short answer: 1
Calculation: 2
Total: 4

Sample questions

Original practice questions written in the style of the exam.

Question 13 marks
(a) State the difference between a scalar quantity and a vector quantity.

(b) A runner completes exactly one lap of a 400 m circular track in 80 s. State the runner's average speed and average velocity for the lap, and explain why they differ.
Mark scheme
- A scalar has magnitude only; a vector has magnitude and direction (1)
- Average speed $= 400/80 = 5.0\,\text{m s}^{-1}$ (1)
- Average velocity $= 0$ because the displacement after one full lap is zero (1)
Question 23 marks
A stone is thrown vertically upwards at $14.0\,\text{m s}^{-1}$ from the edge of a cliff. The point of release is $25.0\,\text{m}$ above the sea. Air resistance is negligible.

Calculate the time taken for the stone to reach the sea. Give your answer to 2 significant figures.
Mark scheme
- Uses $s = u t + \frac{}{}$ with a consistent sign convention, e.g. (1)
Question 35 marks
A football is kicked from level ground with a velocity of $18.0\,\text{m s}^{-1}$ at $35^\circ$ above the horizontal. Air resistance is negligible.

(a) Calculate the maximum height reached by the ball.

(b) Calculate the horizontal distance travelled by the ball before it lands.
Mark scheme
- Vertical component and horizontal component (1)

1

2

a

t^{2}

s = ut + \tfrac{1}{2}at^2

s = u t + \frac{1}{2} a t^{2}

-25.0 = 14.0t - 4.905t^2

Rearranges to

4.905t^2 - 14.0t - 25.0 = 0

and solves the quadratic (1)

t = 4.1\,\text{s}

(1)

u_v = 18.0\sin 35^\circ = 10.3\,\text{m s}^{-1}

u_{v} = 18.0 sin 3 5^{\circ} = 10.3 m s^{- 1}

u_h = 18.0\cos 35^\circ = 14.7\,\text{m s}^{-1}

Uses

v^2 = u^2 + 2as

with

v = 0

at the top:

h = \dfrac{10.3^2}{2 \times 9.81}

(1)

h = 5.4\,\text{m}

(1)

Time of flight

t = \dfrac{2 \times 10.3}{9.81} = 2.10\,\text{s}

(1)

Range

= 14.7 \times 2.10 = 31\,\text{m}

(1)