Determining speed Flashcards
What can you measure the speed of falling objects with?
light gates
What is the acceleration due to gravity on Earth and what does it mean?
10 m/s²
A falling object will increase its speed by 10 m/s every second when falling (in the absence of frictional or resistive forces).
What is the typical speed for these activities?
a) walking
b) running
c) cycling
d) driving
a) 1.5 m/s
b) 3.0 m/s
c) 6.0 m/s
d) 14 m/s
Describe how you can determine the average speed of a moving trolley as it moves down a slope.
When you know the distance that a body moves, and the time taken for the body to move that distance,
you can use the equation speed = distance ÷ time to determine it’s speed.
This can be done by measuring the distance between two points - that the trolley moves past, and dividing it by the time taken to travel between those points,
or by using light gates to measure the time for which a known length of card breaks a light beam.
State what you need to measure to determine the speed of an object.
time taken for the object to travel over a known distance
Explain how two light gates can be used to find the acceleration of a ball rolling down a slope.
Calculate the speed of the ball through the first light gate using speed = distance ÷ time.
Calculate the speed of the ball through the second light gate.
Work out the change in speed and the time difference between the two light gates.
Calculate the acceleration using the equation acceleration = change in speed ÷ change in time.
Describe how a falling ball can be used to find an accurate value for the acceleration due to gravity, g.
Answer should include reference to:
measurement of height, h, through which a ball will fall vertically;
the time taken for the ball to fall through the height, h;
the use of the equation g = 2h/t² to find g;
repeat values being taken;
and an average value being calculated and compared to g;
the falling object must accelerate and not reach terminal velocity during the fall.
