OCR A-Level Physics B H557
Planning
Implementing
Analysis
Evaluation
Practical Skills
Use of Apparatus and Techniques
Fundamental Data Analysis
Imaging and Signalling
Sensing
Mechanical Properties of Materials
Waves and Quantum Behaviour
Space, Time and Motion
Creating Models
Out Into Space
Our Place in the Universe
Matter: Very Simple
Matter: Hot or Cold
Electromagnetism
Charge and Field
Probing Deep Into Matter
Ionising Radiation and Risk
Out Into Space
Motion in a uniform gravitational field
- 3 things to know
- Components 01, 02 and 03
Overview
Recall questions on field lines and equipotentials, showing newtons per kilogram equals metres per second squared, treating projectile motion as two independent directions, and where this approximation fails.
What you need to know
Answer each one before you reveal it.
Why do all objects in free fall near the Earth have the same acceleration?
A ball thrown horizontally at 15 m s⁻¹ falls for 2.0 s. How far horizontally does it travel?
Questions from this subtopic
Each one with the model answer underneath.
- 1
What is a uniform gravitational field?
Model answer
It is a region in which the gravitational field strength has the same magnitude and direction everywhere.
- 2
How are the field lines of a uniform gravitational field arranged?
Model answer
They are parallel, equally spaced and directed vertically downwards.
- 3
State the value and unit of the gravitational field strength near the Earth's surface.
Model answer
It is about 9.81 N kg⁻¹, directed vertically downwards.
- 4
Why do all objects in free fall near the Earth have the same acceleration?
Model answer
The gravitational force is proportional to mass, so the acceleration found from force divided by mass is the same for every mass.
- 5
Show that N kg⁻¹ is equivalent to m s⁻².
Model answer
A newton is a kilogram metre per second squared, so a newton per kilogram is a metre per second squared, and field strength and free-fall acceleration are numerically equal.
- 6
How are the horizontal and vertical motions of a projectile treated?
Model answer
They are treated as independent, the horizontal velocity staying constant while the vertical motion accelerates downwards at g.
Other ways to work this
The same content, four other ways.
What is inside Levo
Six ways to work the same material.
Every question in Out Into Space, on a schedule.
Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.
Or £46 a year, about £3.83 a month. Cancel anytime.