Newtons Laws of Motion

The most common example is that you throw a ball at the wall, it comes back to you.

You do the action and then wall does the reaction by returning the ball with equal magnitude but in a direction opposite to your action.

Using the equation for acceleration a = F/m, where F is the net force and m is the mass, we can find that the acceleration of the box is 2 m/s^2. Using the equation v = at, where v is the final velocity, a is acceleration, and t is time, the speed of the box at the end of the 5 second interval is 10 m/s.

Use the formula v2=u2+2*a*s

v=final velocity

u=intital velocity

a=acceleration due to gravity

s=displacement

This then gives:

2*9.8*5

=98

square root of 98

9.89ms-1

Velocity change can result in changes in an object's speed and/or direction of motion. This change in velocity can be caused by forces such as acceleration, deceleration, or changes in direction, which can affect the object's kinetic energy and momentum.

Friction is a force that opposes the motion of an object. The net force on an object is the sum of all the forces acting on it, including friction. If the net force is greater than friction, the object will accelerate. If friction is greater than the net force, the object will not accelerate and may start sliding on the surface due to the imbalance of forces.

Scalar is a type of quantity which contains magnitude only and has no direction.

For example: distance and speed

Balanced forces do not cause changes in an object's motion or acceleration. When two forces are balanced, their magnitudes and directions cancel each other out, resulting in no net force acting on the object.

How much force is needed to bring a 3200 lb car from rest to a velocity of 44ftsec in 8 sec?

a = (vf - Vi)/time

a = (0 - 44)/ 8

a = -5.5 m/s^2

F = m * a

Since the weight is given in pounds, gravity = 32.2 m/s^2

W = m*g

3200 = m * 32.2

m = 99.4 Slugs

At least that is what we used to call mass in the English system

F =99.4 * -5.5

F = -546.7 lbs.

As strange as it may seem at first, the ball is actually moving towards the center, its just that when the centripetal force pulls the ball towards the center, the objects preexisting speed moves it to another spot on the circle, stopping it from actually spiraling inwards.

One way to visualize this is to imagine that you throw a ball. Under normal circustance, when you throw the ball, it will go forward for a little bit but it will eventually be pulled down by gravity and hit the ground. Now, imagine that you could throw the ball so fast that by the time it falls 10 feet, it has gone far enough out form the Earth that there is another 10 feet to go before it reaches the ground. Thus, even though the ball is getting pulled towards the Earth, its falling as fast as its moving.

Its this combination of falling and moving that actually creates the circular motion. If the falling is faster than the moving, the object will just eventually spiral into whatever is pulling on it. Alternatively, if the moving is faster than the pulling, there will be an overall hyperbolic path, as the object gets close to the source of the pul but then shoots away.

The 1st law says that changes in motion are caused by forces.

The 2nd law says that the force applied to an object causes acceleration.

The 3rd law says that when a force is applied it causes equal and opposite changes in momentum so that the vector sum of momentum is zero.

A body moving at a uniform speed may have a uniform velocity, or its velocity could be changing. How could that be? Let's look. The difference between speed and velocity is that velocity is speed with a direction vector associated with it. If a car is going from, say, Cheyenne, Wyoming to the Nebraska state line at a steady speed of 70 miles per hour, its velocity is 70 miles per hour east. Simple and easy. Uniform speed equals uniform velocity. (Yes, I-80 isn't perfectly straight there. Let's not split hairs.) But a car moving around a circular track at a uniform speed is constantly changing direction. Its speed is constant, but its velocity is changing every moment because the directionit is going is changing. Speed is uniform, but velocity isn't. As asked, uniform speed is a uniform distance per unit of time. And this will yield a uniform distance per unit of time in its velocity, but the direction vector may be uniform or it may be changing each moment, as illustrated.

All Forces! For every action there is an equal and opposite reaction.
"The size of the forces on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. Forces always come in pairs - equal and opposite action-reaction force pairs"

The force of friction is equal and opposite to the applied force in this scenario, so the force of friction on the object would also be 20N. This allows the object to remain in a state of equilibrium and not accelerate.

1. A ball rolling on a flat surface will continue rolling at a constant velocity unless acted upon by an external force.
2. A stationary object will remain at rest, and an object in motion will continue moving in a straight line at a constant speed unless acted upon by an external force.
3. If a car suddenly stops, passengers inside the car will continue moving forward due to inertia until a seatbelt or airbag provides the necessary force to stop them.

the buoyant force will remain the same because the rock will displace the same amount of water volume at any depth.

Theoretically, it will gain buoyancy as it sinks, because when an objects density matches the density of the water around it, and water becomes denser as it falls deeper, it will be neutrally buoyant or floating. But since a rock is always going to be more dense than water it would still sink.

The mass of the object can be calculated using the formula F = ma, where F is the net force, m is the mass, and a is the acceleration. Rearranging the formula to solve for mass, we get m = F / a. Plugging in the values given, mass = 120N / 1.5 m/s^2 = 80 kg. So, the mass of the object is 80 kg.

The angle of the resultant force can be calculated using trigonometry principles such as the Pythagorean theorem and inverse trigonometric functions. Given the magnitudes of the two component forces, you can determine the angle using the formula: angle = arctan(opposite/adjacent). This will help you find the direction in which the resultant force is acting.

Friction force is equal to the force applied only when the object is not moving or it is just beginning to slide. Once the object has started motion completely, it means that the force applied has exceeded the frictional force

The law of unbalanced forces states that when two forces acting on an object are not equal in magnitude and opposite in direction, the object will accelerate in the direction of the greater force. This is described by Newton's second law of motion, which states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.

While the forces between the truck and trailer are equal in magnitude and opposite in direction, they act on different objects (truck and trailer) resulting in acceleration of the entire system. The truck exerts a force on the trailer causing it to accelerate forward, and in return, the trailer exerts an equal and opposite force on the truck. As both objects have different masses, this results in them accelerating in the direction of the larger force, which is from the truck to the trailer.

Newton's second law of motion (F=ma) explains how a force acting on an object will cause it to accelerate. In terms of vehicle safety, this law is crucial because it helps engineers design vehicles with the right balance of mass and acceleration to ensure they can stop or maneuver safely in various driving conditions. Understanding this law also helps in designing safety features like airbags and seatbelts to protect occupants in case of a collision.

Unbalanced forces are important in order to move anything. An object under balanced forces does not move. For example as you sit in your chair reading this, gravity is exerting a force on your body downwards but your chair balances this force by exerting a force upwards on you that is equal and opposite to the force of gravity. These two forces oppose each other and therefore you do not move. In tennis in order to change the direction of a tennis ball you need to exert a net force(an unbalanced force) in the direction you want the tennis ball to move. In tennis there are also unbalanced torques(a force acting at a distance from a pivot point) on the ball that cause the ball to spin. Hope that helps.