Effects of Forces Flashcards
Give three examples of non-contact forces.
- Gravity
- Magnetism
- Electrostatic charge
Give two examples of contact forces.
- Weight
- Friction
How do you draw a scale drawing to resolve a force into its horizontal and vertical components?
1) Decide on an appropriate scale (If the force is 50N, make 1cm 10N)
2) Draw the line to represent the force at the correct given angle.
3) Draw the horizontal and vertical components
4) Measure the lengths of the components and convert them to N by using your scale.
What does a free-body force diagram represent?
It represents all the forces acting on a single body.
What is a resultant force?
It is a single force that determines whether a body will be stationary, accelerating, or moving at a constant speed.
If there are two forces acting in the same direction, what do you do to find the resultant force?
¦ ¦ ———-> 10N
¦ ¦ ————–> 20N
¦ ¦ ———-> 10N
—————–
If there are two forces acting in opposite directions, what do you do to find the resultant force?
Minus the forces.
If there are two forces acting at a right angle, how do you find the resultant force?
- A scale drawing/diagram
- Pythagoras’ theorem
What is a moment?
The forces which cause a turning effect or rotation at a distance from the pivot.
- It is measured in newton-metres (Nm)
What is the equation to find a moment?
Moment = Force x distance from the normal
M = F x d
What is the equation for moments in equilibrium for rotational forces?
sum of the = sum of the
clockwise moments anticlockwise moments
Levers can cause rotation. What does the nature of this rotation depend on?
The position of:
- The input force
- The output force
- The fulcrum
What is a high gear?
A large input gear turns a small output gear.
- This causes a high speed and low turning effect.
What is a low gear?
A small input gear turns a large output gear.
- This causes a low speed and high turning effect.
