Column 1
fundamental force that attracts any object with mass towards another object with mass is known as ...........
Gravity
Area of circle
pi r2
An accelerating object is an object which is changing its ...............
velocity
Formula for circumference
c = 2 pi r
Any force on an object that keeps it undergoing uniform circular motion is
Centripetal Force
velocity of an object in a straight line
Linear velocity
On the surface of the Earth, "g" has the magnitude of
9.8m/ s
The centripetal force refers to any force or combination of forces that produces a
centripetal acceleration.
Rotation
If the axis is located within the turning body (internal), the motion is called a rotation.
the rate of change of angular displacement of an object per unit of time
Angular velocity
.................... provides the centripetal force necessary for a car to travel around a flat circular racetrack.
Friction
Motion along a circular path with change in rate of rotation is called..........................
non uniform motion
.................. does not change when gravity changes whereas ........................ changes
Mass; Weight
Calculate the angular velocity of a 0.230 m radius bus tyre when the bus travels at 15.0 m/s. [USE formula, v = r omega]. give the correct units
65.2rads-1
If the axis is located outside of the turning body (external), the motion is called
Revolution
Two characteristics of "Centripetal Acceleration"?
1. Perperndicular to the velocity
2. Points towards the centre of the curve
Uniform circular motion characteristics?
magnitude of velocity is constant whereas direction is not
Linear motion : Rotational motion - what is it for speed, "s"; velocity, "v" and time, "t"
s = theta; velocity = omega; time = time
The further an object moves from the surface of the Earth, the less gravity it feels from the Earth. This is known as ....................
Microgravity
To prevent skidding and damages to tyre the roadbed ahs to be inclined by ................
raising outer edge over inner
Determine the angular velocity if 2 revolutions are completed in 2 seconds.
Angular displacement, omega = theta/ time
6.3 radians/ sec
If a wheel moves at 10 m/sec, and its angular velocity is 5 radians/sec, calculate the radius of the wheel.
[USE formula: V = 'r' x 'omega'
10 = r x 5; or, r = 10/ 5 = 2m
Newton's 1st Law of Motion?
an object at rest will remain at rest, and an object in motion will continue in motion with the same speed and direction unless acted upon by an unbalanced external force; essentially, an object resists changes in its state of motion unless a force is applied to it.
A speed skater goes around a turn with a 24 m radius. The skater has a speed of 11m/s and experiences a centripetal force of 460N. What is the mass of the skater?
[USE the formula: F = ma and a = v2/ r]
91.3kg
Calculate the gravitational force between a 30kg person and a 70kg object that are 3 meters apart. [USE the formula: F = Gm1m2/ r2. G = 6.67 x 10-11Nm2/ kg2]
1556.33 x 10-11= 1.55/ 1.6 x 10-8N