Forces, Motion and Pressure MTA Flashcards
What two things does a force arrow show?
- The length of the arrow shows the size of the force.
- The direction of the arrow shows the direction of the force.
Give some examples of non-contact forces
- Gravitational force
- Electrostatic force
- Magnetic force
Give some examples of contact forces
- Friction
- Air resistance
- Tension
- Normal contact force
What are the units for:
a) gravitational field strength
b) weight
c) mass
a) N/kg
b) N
c) kg
What equation links weight, mass and gravitational field strength?
Weight = mass x gravitational field strength
W = m g
What type of energy is stored in a spring that is stretched or compressed?
Elastic potential energy
What happens to the temperature of an object experiencing friction?
Temperature increases
What is the name of an object that:
a) will return to its original shape after being deformed
b) will not return to its original shape after being deformed
a) elastic
b) inelastic
What is the relationship between force and extension of an elastic object?
Directly proportional
What happens to air resistance as speed increases?
As speed increases, air resistance increases.
What are typical speed values for someone walking, running and cycling (m/s)?
- Walking 1.5 m/s
- Running 3 m/s
- Cycling 6 m/s
What is the speed of sound?
340 m/s
How many forces need to to be applied to this spring to stretch or compress it?
Two forces (e.g. one at either end)
What equation links distance travelled, speed and time?
Distance travelled = speed x time
s = v t
Describe the motion in the following distance-time graph at point (a).
a) constant speed
Describe the motion of a moving car experiencing balanced forces.
Keep moving at a constant speed
Describe the motion of a moving car experiencing unbalanced forces.
The car will change speed (either accelerate or decelerate)
Describe the motion of a stationary car experiencing balanced forces.
The car will remain stationary.
Describe the motion of a stationary car experiencing unbalanced forces.
The car will accelerate.
What are typical everyday speeds for cars, trains and planes?
- Car 25 m/s
- Train 55 m/s
- Plane 250 m/s
If your mass on Earth is 50 kg, what would be your mass on the moon?
The same, 50 kg.
Your mass does not change.
Name the forces acting on the book.
Weight (downwards)
Normal contact force (upwards)
Describe the experiment to investigate how force affects the extension of the spring.
- Measure the starting length of the spring using the ruler.
- Add one 10 g mass, measure the extension of the spring using the ruler.
- Repeat 5 times, each time adding one 10 g mass and measuring the extension of the spring.
Name the equipment used to measure forces
Newtonmeter
When oil or grease is used to reduce friction, what is this called?
Lubrication
