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Free- body Diagram. Homework. To a 10.0-kg table, three forces were applied on it. F1 = 5.00 N, South F2 = 6.00 N, East F3 = 4.00 N, West Using the component method, what is the net force applied on the table?. Homework. To a 10.0-kg table, three forces were applied on it.
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Homework To a 10.0-kg table, three forces were applied on it. F1 = 5.00 N, South F2 = 6.00 N, East F3 = 4.00 N, West • Using the component method, what is the net force applied on the table?
Homework To a 10.0-kg table, three forces were applied on it. F1 = 5.00 N, South F2 = 6.00 N, East F3 = 4.00 N, West 2. If a fourth force was applied and made the net force zero, what is the magnitude and direction of this fourth force?
Homework Provide the FBD of the system (in red text) in the following scenarios and identify the agents of all forces cited. • a stone in midair after thrown upwards • a balloon-powered car moving at a constant speed • a balloon-powered car moving with a completely deflated balloon
Homework • A certain balloon-powered car has a mass of 50.0 grams. The gushing air from its balloon provides a thrust force of 0.30 Newton. If the car is accelerating at 2.00 m/s2for the first 5.00 meters, do you think friction is acting on the car? Defend your answer by showing your solutions.
Objectives • Recall the Laws of Motion. • Construct the free-body diagram of the forces acting on a body. • Determine the magnitude of forces acting on a body.
Laws of Motion In memory of thepastlesson…
Can you remember? What are the three laws of motion proposed by Einstein?
Can you remember? What are the three laws of motion proposed by Isaac Newton?
What law has this provision? For every action, there is an equal but opposite reaction.
What law has this provision? Every body continues in its state of rest, or of motion in a straight line at constant speed, unless it is compelled to change that state by a net force exerted upon it.
What law has this provision? The acceleration produced by a net force on a body is directly proportional to the magnitude of the net force, is in the same direction as the net force, and is inversely proportional to the mass of the body.
Balloon-powered Cars ALIN ANG NAIBA?
Balloon-powered Cars As the air is expelled from the balloon, the car moves. What are the forces acting on it?
Free-body Diagram A free-body diagram is a physical model that represents all forces acting on a system.
Some Types of Forces • Weight - the gravitational pull of the earth • Friction - the contact force that acts to oppose sliding motion between surfaces • Normal - the contact force exerted by a surface on an object • Thrust - a general term for the forces that move objects Read p. 94 of Glencoe for the complete list.
When constructing the FBD, Always identify the SYSTEM.
Balloon-powered Cars As the air is expelled from the balloon, the car moves. What are the forces acting on it?
Balloon-powered Cars As the air is expelled from the balloon, the car moves. What are the forces acting on balloon-powered car?
How would one know that a force should be in the FBD? For every force there should be an AGENT.
How would one know that a force should be in the FBD? If you cannot identify the agent that applies or causes the force, then that force should not be part of the FBD.
Balloon-powered Cars What are the agents applying these forces?
Quantitative FBD • Construct the FBD. Masses Bear = 120 g Table = 12 kg
125 g W = 1.23 N 355 g W = 3.48 N 25.0 kg W = 245 N 1. Determine the magnitude of the weight (in Newton) of the following: a. star b. blue pillow c. table
125 g Fn = 1.23 N 355 g Fn = 4.70 N 25.0 kg Fn = 250. N 2. Determine the normal force acting on the following: a. star b. blue pillow c. table
Simple Drills F applied = 20.0 N f = 20.0 N Describe the direction of the system if it is at rest.
Simple Drills F applied = 20.0 N f = 20.0 N Describe the velocity of the system if it is at rest.
Simple Drills F applied = 20.0 N f = 20.0 N Describe the velocity of the system if it is moving 30 m/s.
Simple Drills F applied = 20.0 N Describe the direction of the system if it is moving.
Simple Drills F applied = 20.0 N Describe the velocity of the system if it is moving.
Seatwork • Use a piece of size 4. • Listen to the instructions carefully.
Number 1 f = 15.0 N Describe the motion of this body moving to the right. (speeding up, slowing down, constant velocity)
Number 2 F applied = 20.0 N f = 15.0 N Describe the motion of this body moving to the right. (speeding up, slowing down, constant velocity)
Number 3 F applied = 20.0 N f = 15.0 N What is the net force acting on the body (magnitude and direction)?
Number 4 F applied = 20.0 N f = 15.0 N If the body has a mass of 5.00 kg, what is its acceleration (magnitude and direction)?
Number 5 F applied = 15.0 N f = 15.0 N How many seconds will it take for this body to increase its speed by 5.00 m/s?