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Two forces are exerted on an object of mass m in the x direction as illustrated in the unlabeled force diagram below. Assume that these are the only forces acting on the object.

JWhich of the curves labeled A to D on the graph below could be a plot of x t , the position of the object along the x axis as a function of time? Q: You are on the roof of a Physics Building, 12 m above the ground. Your physics professor, who is 1. What quantities are perdendicular for an object in uniform circular motion? See picture. Q: What is the angular speed in rpm with which the Earth spins on its axis?

What is the angular speed A: Angular speed of earth's spin and revolution around sun need to be calculated. Q: An airplane accelerates down a run at 3.

Q: then turns North again 4. A runner goes North for 3 km, then turns and heads South for for 4 km. Q: A juggler throws a bowling pin straight up with an initial speed of 5. Q: Problem A solid uniform ball with mass m and diameter d is supported against a vertical frictionless Q: A battery having an emf of 9. Q: Two forces are exerted on an object of mass m in the x direction as illustrated in the unlabeled for A: In this, there are more than one question so we will solve first question for you.

Q: Show that when body is dropped from a height h ft above the ground, its velocity v neglecting air r A: This is a equation from kinematics. Q: Find the y-component of this vector: Q: Q3- Calculate the mass defect and binding energy per nucleon for the nuclide 1K.

Q: A hoverboard rider goes straight down Arkansas Avenue for 2 miles, then turns left and goes straight Q: The resultant of the three parallelforces P, 2P and 3P, with their corresponding locations, is denot A: As per our guidelines we can solve only a single problem.

For the second problem you can post the qu Q: Three point charges are located on a circular arc as Q2 shown in Figure P Q: A girl on a skateboard total mass of Q: Two uncharged spheres are separated by 2. Q: Which method will help us find the magnitude of the resultant vector of two vectors aligned perpendi A: Answer:- d Pythagorean theorem The magnitude of the resultant vector of two vectors aligned per The graph above descri Q: Simulate the motion of an idealized projectile in PhysLab.

What is the range of the shuttlecock laun If Upton free falls for 2. A: Write the co-ordinates for all three points A,B and C. A: We need to show a 1 hour in min ,s, day, year and ms. Q: A plane, diving with constant speed at an angle of Q: Supply all missing information with the correct numerical values.

Do not include the units. Round of Learning Goal: To understand the concept of force as a push or a pull and to become familiar with everyday forces. A force can be simply defined as a push or a pull exerted by one object upon another. Each force acts upon some other object. The action of a force can be visualized as a push or a pull. Since each force is created by one object and acts upon another, forces must be described as interactions.

Each force has a direction: Forces are vectors. The main result of such interactions is that the objects involved change their velocities: Forces cause acceleration. However, in this problem, we will not concern ourselves with acceleration--not yet.

Some common types of forces that you will be dealing with include the gravitational force weight , the force of tension, the force of friction, and the normal force. It is sometimes convenient to classify forces as either contact forces between two objects that are touching or as long-range forces between two objects that are some distance apart. Contact forces include tension, friction, and the normal force. Note that such a distinction is useful but not really fundamental: For instance, on a microscopic scale the force of friction is really an electromagnetic force.

In this problem, you will identify the types of forces acting on objects in various situations. First, consider a book resting on a horizontal table. Part A Which object exerts a downward force on the book? A string is attached to a heavy block. The string is used to pull the block to the right along a rough horizontal table.

Part G Which object exerts a force on the block that is directed toward the right? Part I What is the force acting on the block and directed to the right called? The same block is placed on the same rough table. However, this time, the string is disconnected and the block is given a quick push to the right. The block slides to the right and eventually stops. The following questions refer to the motion of the block after it is pushed but before it stops. Part M How many forces are acting on the block in the horizontal direction?

ANSWER: 0 1 2 3 Once the push has commenced, there is no force acting to the right: The block is moving to the right because it was given a velocity in this direction by some force that is no longer applied to the block probably, the normal force exerted by a student's hand or some spring launcher. Once the contact with the launching object has been lost, the only horizontal force acting on the block is directed to the left--which is why the block eventually stops.

Once the block stops, fricion becomes zero assuming the table is perfectly horizontal. Newton's Principia states this first law of motion: An object subject to no net force maintains its state of motion, either at rest or at constant speed in a right line.

This law may be stated as follows: If the sum of all forces acting on an object is zero, then the acceleration of that object is zero.

Mathematically this is just a special case of the 2nd law of motion, when , prompting scholars to advance the following reasons among others for Newton's spelling it out separately: 1. This expression only holds in an inertial coordinate system--one that is not accelerating--and this law really says you have to use this type of coordinate system i.

This was a direct challenge to the Impetus theory of motion, described as follows: A mover, while moving a body, impresses on it a certain impetus, a certain power capable of moving this body in the direction in which the mover set it going, whether upwards, downwards, sideways or in a circle. By the same amount that the mover moves the same body swiftly, by that amount is the impetus that is impressed on it powerful.

It is by this impetus that the stone is moved after the thrower ceases to move it; but because of the resistance of the air and the gravity of the stone, which inclines it to move in a direction opposite to that towards which the impetus tends to move it, this impetus is continually weakened. Therefore the movement of the stone will become continually slower, and at length, the impetus is so diminished or destroyed that the gravity of the stone prevails over it and moves the stone down towards its natural place.

Newton's 1st law is often very difficult to grasp because it contradicts various common-sense ideas of motion that they have acquired from experinece in everyday life.

For example, unnaccounted for forces like friction might cause a ball rolling on the playground to eventually stop, even though no obvious forces seem to be acting.

When studying Newtonian mechanics, it is best to remember this as two laws: 1. If the net force i. If an object is moving with constant velocity not speed , that is, with zero acceleration, then the net force acting on that object must be zero.

Complete the following sentences to see if you can apply these ideas. Relating Graphs and Free-Body Diagrams Two forces are exerted on an object of mass in the x direction as illustrated in the free-body diagram. Assume that these are the only forces acting on the object. Part A Which of the curves labeled A to D on the graph could be a plot of , the velocity of the object in the x direction as a function of time?

Hint A. But accelerating doesn't necessarily mean speeding up. The effect of the acceleration in the x direction on the object was to 1. Part B Which of the curves labeled A to D on the graph could be a plot of , the position of the object along the x axis as a function of time? Hint B. The graphs in Parts A and B were not the only possible velocity and position graphs for the given net force.

However, all graphs illustrating motion under the influence of a constant force will have the same characteristics. This caused the velocity graph to be a linear curve of constant slope i. When velocity obeys a linear relationship, the position of the object follows a curve whose shape is quadratic also called parabolic. You saw examples of this type of motion when you studied motion under constant velocity in an earlier chapter.

Conceptual Questions on Newton's 1st and 2nd Laws Learning Goal: To understand the meaning and the basic applications of Newton's 1st and 2nd laws. In this problem, you are given a diagram representing the motion of an object--a motion diagram. The dots represent the object's position at moments separated by equal intervals of time.

The dots are connected by arrows representing the object's average velocity during the corresponding time interval. Your goal is to use this motion diagram to determine the direction of the net force acting on the object. You will then determine which force diagrams and which situations may correspond to such a motion. Part A What is the direction of the net force acting on the object at position A? Therefore, the acceleration is zero--and so is the net force. Part B What is the direction of the net force acting on the object at position B?

The velocity is directed to the right; however, it is decreasing. Therefore, the acceleration is directed to the left--and so is the net force. Part C What is the direction of the net force acting on the object at position C? Hint C. The horizontal component of the velocity does not change. The vertical component of the velocity increases.

Therefore, the acceleration--and the net force--are directed straight downward. The next four questions are related to the force diagrams numbered 1 to 6. The number next to each arrow represents the magnitude of the force in newtons. Part D Which of these diagrams may possibly correspond to the situation at point A on the motion diagram? Type, in increasing order, the numbers corresponding to the correct diagrams. For instance, if you think that only diagrams 3 and 4 are correct, type Part G.

A car is moving along a straight road at a constant speed. A car is moving along a straight road while slowing down. A car is moving along a straight road while speeding up. A hockey puck slides along a smooth i.

A hockey puck slides along a rough concrete surface. A cockroach is speeding up from rest. A rock is thrown horizontally; air resistance is negligible. A rock is thrown horizontally; air resistance is substantial. A rock is dropped vertically; air resistance is negligible. A rock is dropped vertically; air resistance is substantial. Part H Which of these situations describe the motion shown in the motion diagram at point A?

Type the letters corresponding to all the right answers. For instance, if you think that only situations C and D are correct, type CD. The net force acting on it is constant and nonzero. There are no forces at all acting on it.

There is only one force acting on it. If there is a net force acting on a body, regardless of whether it is a constant force, the body accelerates. If the body is at rest and the net force acting on it is zero, then it will remain at rest. The net force could be zero either because there are no forces acting on the body at all or because several forces are acting on the body but they all cancel out. Part B If a block is moving to the left at a constant velocity, what can one conclude?

The net force applied to the block is directed to the left. The net force applied to the block is zero. There must be no forces at all applied to the block. If a body is moving with constant velocity, then it is not accelerating and the net force acting on it is zero.



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