Concepts and Vocabulary
Apparent Weight
Friction
Tension
Inclines
Elastic Force
100
Force perpendicular to surface
Normal Force
100
If an elevator accelerates upwards, a rider's apparent weight will...
Be larger than their actual weight.
100
All else being equal, a _______________ will experience a greater force of friction than a _______________ one does.
heavier, lighter
100
Direction that tension always points
Towards the other end of the string / wire / rope / cable
100
True or false: The longer the ramp, the lower the applied force required to push an object up that ramp.
True
100
Name for the equation that allows one to calculate the elastic force.
Hooke's Law
200
Calculated by taking the slope of a force / displacement graph for an elastic object.
Spring Constant
200
When an elevator is moving at constant velocity downwards, a rider's apparent weight is...
The same as their actual weight.
200
Two ways that the force of friction between two objects can be reduced.
- Make surfaces smoother
- Place a layer of liquid between the two objects
- place wheels or other rolling objects between the two objects.
200
If pulling an object with a rope, the greater the force of friction between the object and the surface, the ________________ the tension in the rope will be.
Greater
200
All else being equal, the __________________ the ramp, the more likely an object placed on that ramp will be to slide down the ramp.
Steeper
200
Spring A and Spring B have the same spring constant. The force required to compress Spring A by 5cm will be ______________ the force required to stretch Spring B by 5cm.
The same as
300
Type of friction that resists an object starting to move.
Static Friction
300
A 65kg person is in an elevator moving upward at a constant 5.0m/s. Their apparent weight will be...
640N
300
A 75kg object is pushed with a force of 350N. If it accelerates at 0.90m/s2, what is the coefficient of friction between the object and the surface?
0.38
300
A 7.5kg box is connected to a 12.5kg box by a rope. If they are pulled across a frictionless surface by a force of 17N, what is the tension force in the rope?
6.4N
300
A 15kg block is placed on a frictionless ramp that has a slope of 25 degrees above the horizontal. What is the acceleration of the block?
4.1m/s2 [down the ramp]
300
What is the spring constant of the spring in a scale if it compresses by 15cm when a mass of 35kg is placed on the scale?
2300N/m
400
This variable will be smaller the smoother the surface is.
Coefficient of friction (mu)
400
What is the apparent weight of a 75kg astronaut in a rocket that accelerates upwards at 22.5m/s2?
2400N
400
The coefficient of static friction between a 101kg object and the surface it is sitting on is 0.275. What is the minimum amount of force required to make this object move?
>273N
400
A 12kg box is pulled across a floor with a tension force of 75N at an angle of 32 degrees above the horizontal. If the coefficient of friction between the box and the floor is 0.260, what is the acceleration of the box?
3.6m/s2
400
What is the minimum coefficient of static friction that can prevent a 125kg object from sliding down a 35 degree ramp?
Coefficient of static friction must be greater than or equal to 0.70.
400
The spring in a car has a spring constant of 45000N/m. If each of the four springs in a car bears one quarter of the car's weight, how much does each spring compress, in centimetres, if the car's total mass is 1250kg?
6.8cm
500
Component of gravity that will cause an object to slide on an inclined plane.
F (parallel)
500
An amusement park drop ride accelerates from rest to falling at 35m/s in 4.5s. What is the apparent weight of a 55kg rider during this time?
110N
500
A 1250kg car slams on the brakes and slides to a stop. If the skid marks on the pavement are 37.5m long, and the coefficient of friction between the tires and the road is 0.506, how fast, in km/h, was the car travelling when it slammed on the brakes?
69.4km/h
500
A 45kg weight (A) and a 32.5kg weight (B) are connected by a rope and hung from a frictionless pulley. What is the force of tension in the rope?
370N
500
If the ramp has an angle of 37.5 degrees, A has a mass of 125kg, B has a mass of 97.5kg, and the system is entirely frictionless, what is the tension in the rope?
864N
500
What is the acceleration of a 20.0g arrow if the bow that launches it has a spring constant of 6.75N/m and the bow is bent by 45.0cm? Disregard air resistance.
152m/s2