2. 1. Do all forces result in movement?
2. What do you think is the net force in
the example below?
3. Why?
LET’S RECALL!
Balanced Forces
NO!
ZERO!
Because the acting
forces are equal and in
opposite direction and
there is no movement!
4. Does the example below show
balanced forces?
Weight of the
boat with people
pulling down
(gravity)
Water pushing up the boat
(buoyancy/resistance)
LET’S RECALL!
YES
5. What do you think could happen if the
forces acting here will be unequal?
Consider this!
6. The boat will sink!
Which is very dangerous to passengers.
Consider this!
7. So, what is
meant by
unbalanced
forces?
the two interacting forces are not equal, so
that there is a movement in one direction.
8. Examine this tug of war.
Each person can pull with exactly (1) force.
1. What is the force for the team on the left side?
2. What is the force for the team on the right side?
3. Which direction will the rope move?
3 forces
2 forces
To the left
3 forces 2 forces
9. 1. What forces are interacting here?
2. Which has greater force?
3. How can you tell?
Because the car moves towards the direction of the tires’ rotation.
Car’s tires rotating towards right
Friction from the ground
opposing the tires
Examine the
moving car.
24. 2. Draw and label
the arrow of the
interacting forces.
1. Balanced or
Unbalanced
Forces?
Unbalanced forces
Thrust of rocket engines
Pull of gravity
25. force of gravity
air resistance
3. How can we slow
“hippo” down?
Answer:
Increase air resistance by
giving “hippo” a bigger or
larger parachute.
26. ASSIGNMENT:
Suppose, Superman and Hulk are pulling a truck at
the same time with 20 units of force each. What is
the net force acting on the object?