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physics Newton's law
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Gravity
Terms in this set (22)
A stationary object has no forces acting on it.
fules
An object's inertia causes it to come to a rest position.
fules,Inertia is the tendency of an object to resist change in velocity. It is not a force that causes an object to accelerate or decelerate. A moving object with a lot of inertia (measured by its mass) would actually require more net force to change its velocity in a given amount of time than an object with a low inertia.
Which of Newton's Laws explains why satellites need very little fuel to stay in orbit?
first.Once a satellite is in orbit, the only net force acting on it is the inward force of gravity. The tangential speed of the satellite is just right so that gravity only has the effect of changing the direction of travel. It is a near vacuum in space so the satellite encounters almost no friction to slow them down.
Objects in orbit around the Earth (like a satellite) still have net forces acting on them.
yes,
An object with no net forces acting on it would not have a change in velocity. If it is stationary, it would stay stationary. If it is in motion, it will stay in motion with a fixed velocity (moving in a straight line). This comes directly out of Newton's First Law of Motion.
An object in orbit may have a constant speed, but its direction is constantly changing as it moves in a circle (or ellipse) and, thus, its velocity is also changing (remember, velocity takes into consideration speed and direction). Therefore, there must be a net force acting on it. This is the net force of Earth's gravity acting on the object.
The only way to slow down a moving object is to apply a net force to it.
Velocity will only change if a net force is applied. In this case, you'll slow the speed of the object if you apply a net force in the direction opposite its direction of motion.
Which of Newton's Laws gives the reason for why you can feel things that you touch?
Third Law
Mass is a measure of an object's inertia (or its tendency to resist change in velocity).
True
Objects tend to stay moving because of a force called inertia.
no.inertia is not a force. It is the tendency of an object to resist change in velocity. Mass is a measure of an object's inertia.
normal force
is a force that is directed perpendicular to the two surfaces in contact. It makes sense that the force is perpendicular to the surface since the normal force is what prevents solid
A small car collides with a large truck. Which experiences the greater impact force?
Both the same
In the collision between the car and the truck, which has the greater acceleration?
The car
what is newness first law called?
the law of inertia
Force is
any thing that causes chang in V whither it was it magnatude or dirction
single isolated force cannot exist.
true
The Earth pulls down on us with a force equal to our weight. A falling object will then accelerate with acceleration. This means that as the object falls down.
The Earth accelerate towards the body with acceleration smaller than g
The normal force
is a contact force that is alwaysperpendicular (normal) to the surface
A block of mass mrests on the floor of an elevator that is moving upward at constant speed. What is the relationship between the force due to gravity and the normal force on the block?
N = mg
The block is moving at constant speed, so it must have no net forceon it. The forces on it are N(up) and mg(down), so N= mg, just like the block at rest on a table.
A block of mass mrests on the floor of an elevator that is accelerating upward. What is the relationship between the force due to gravity and the normal force on the block?
N > mg
The block is accelerating upward, so it must have a net upward force. The forces on it are N(up) and mg(down), so Nmustbe greaterthan mgin order to give the net upward force!Follow-up: What is the normal force if the elevator is in free fall downward?
How many forces are involved in the scene shown below of a little box lying on top of the big box lying on the table (Discount the interaction between the table and the ground)? Hint: Start with the little box and work downward. Don't forget that each force should have a Newton's Third Law pair.
6
A box sits in a pickup truck on a frictionless truck bed. When the truck accelerates forward, the box slides off the back of the truck because
No net force acted on the box.
Generally, the reason that the box in the truck bed would move with the truck is due to friction between the box and the bed. If there is no friction, there is no force to push the box along, and it remains at rest. The truck accelerated away, essentially leaving the box behind!
A box of weight 100 N is at rest on a floor where µs = 0.4. A rope is attached to the box and pulled horizontally with tension T = 30 N. Which way does the box move?
f=40N which is greater than the T
The box does not move
A spring of stiffness k is compressed by a distance of x to the right by an external force F
F The magnitude and direction of the spring force are:
F to the left or Ikx| to the left
;