Speed and Acceleration Graphs

CH10 Question 1

Describe the object’s motion in the graph above.

Move a at constant speed for 4 sec, slows down for 3 seconds then speeds up but not to original velocity.

CH10 Question 2

Describe the object’s motion in the graph above.

Move a at constant speed for 4 s, and comes to a rest.

CH10 Question 3

Describe the object’s motion in the graph above.

Positive acceleration for 5 seconds – speeds up.

CH10 Question 4

Describe the object’s motion in the graph

above. Constant speed 150s, const

+accl. For 100 s. Constant speed again for 50 sec, then – accl for one sec.

CH10 Question 4

Calculate the object’s acceleration from

150 to 250 seconds. Vf-Vi/t = 30-10/100= 0,2 m/s2

CH10 Question 4

Calculate the object’s acceleration from

300 to 350 seconds. Vf-Vi/t = 5m/s-30m/s/50 s= -0.5 m/s2

Forces and Motion

Question 1

State Newton’s First Law of motion

An object at rest will remain at rest and object in motion remain in motion unless acted on by a net force.

Question 2

State Newton’s Second Law of Motion

An object will accelerate in the direction of a net force.

Question 3

State Newton’s Third Law of Motion

For every action there is an equal and opposite reaction.

Question 1

What is the equation for calculating Force when you know an object’s mass and acceleration?

Question 1

What is the equation for calculating Force when you know an object’s mass and acceleration?

Force = mass x acceleration

F = ma.

Question 2

What are the units for Force?

Question 2

What are the units for Force? Kg m/s2

N = Newton

Question 3

A sailboat with a mass of 1000 kg is accelerating at a rate of 8 m/s2. What is the force of the wind acting on the sail?

F= ma F = 1000 kg x 8 m/s2 = 8000

N

Question 1

What equation do you use to calculate acceleration if you know the force acting on the object and its mass?

F= ma A = F/m = F m

Question 2

What are the units for acceleration?

m/s2

“meters per second squared”

Question 3

What is the acceleration of a 50Kg swimmer that pushes off the side of the pool with a force of 100N?

a = F/m = 100 kgm/s2 50 kg = 2 m/s2

Question 1

What is the formula used to calculate mass when you know the Force on an object and the resulting acceleration?

F = ma m = F/a = F a

Question 2

A weight lifter accelerates the barbell at a rate of 2.0 m/s2 with an applied force 400N. What is the mass of the barbell?

m = F/a = 400 kg m/s2 5 m/s2

= 80 kg

Question 3

What is the relationship between mass and inertia??

As the mass increases the inertia of an object increases and a greater force will be required to accelerate the object.

Question 1

What is the formula used to calculate the weight of an object on Earth?

weight = mass x gravitational acceleration. Gravitational acceleration on earth = 9.8 m/s2

Question 2

What is the difference between mass and weight?

Mass is a measure of how much matter an object contains.

Weight is a measure of the force of gravity acting on that mass.

Question 3

Calculate the weight of 10 kg of gold sitting on your desk.

weight = mass x ag

ag =9.8 m/s2

W = 10 kg x 9.8 m/s2 = 98 N

Question 1

Name this equation and the variables that compose it.

2

21

d

mmGF

Question 1

Name this equation and the variables that compose it.

Universal Gravitation F = force of gravity G = gravitational constant m = mass of the objects D2 = distance between the objects

2

21

d

mmGF

Question 2

According to the equation what happens to the gravitational force between two objects when they get farther apart?

2

21

d

mmGF

Question 2

According to the equation what happens to the gravitational force between two objects when they get farther apart?

d2 increases and the force of gravity gets smaller.

2

21

d

mmGF

Question 3

According to the equation why does our sun have a gravitational force strong enough to hold all the planets in orbit even though some are very far away.

2

21

d

mmGF

Question 3

According to the equation why does our sun have a gravitational force strong enough to hold all the planets in orbit even though some are very far away.

The sun has a very large mass so its gravitational force is large and far reaching.

2

21

d

mmGF

Question 1

What is the term used to describe an object where the only force acting on the object is gravity ?

Free Fall

Question 2

This is the maximum velocity a falling object will reach as the upward force of air resistance equals the downward force of gravity?

Terminal velocity

Question 3

If an object at terminal velocity is experiencing balanced forces, how can the object still be falling?

Balanced forces only mean that the object is not ACCELERATING, it still falls @ a constant velocity.

Question 1

A fluid includes which three states of matter?

Liquids, gases, and plasmas

Question 2

What is the formula used to calculate pressure and what unit is pressure reported in?

P = mass Area = N/m2 = Pa Usually kPa (kilo Pascals)

Question 3

What is the air pressure if 20 N is exerted over an area of 10m2?

P = mass/Area = 20N 10m2

= 2 Pa

Question 1

According to Bernoulli’s Principal what happens to the pressure of a fluid as the velocity of the fluid increases?

Question 1

According to Bernoulli’s Principal what happens to the pressure of a fluid as the velocity of the fluid increases?

The pressure decreases.

Question 2

What is the upward force exerted on an object immersed in a fluid?

Buoyant force or buoyancy.

Question 3

Archimedes Principal states that for an object to float the weight of the object must be equal to or less than .. . . ?

Question 3

Archimedes Principal states that for an object to float the weight of the object must be equal to or less than .. . . ?

the weight of the fluid displaced by the object.

Question 1

What term is used to describe the resistance of of a gas or liquid to flow?

Viscosity.

Question 2

Hydraulic devices can increase the output force by increasing the output area. Which principal predicts this characteristic?

Pascal’s Principal- the pressure of a liquid in an enclosed system is uniform throughout the system.

Question 3

According to the Venturi effect, what happens to the velocity of a fluid when it is forced to flow through a smaller area??

The velocity of the fluid increases..

Question 1

What is the term for any object thrown or launched from Earth under the influence of gravity?

Projectile

Question 2

Describe the horizontal and vertical forces acting on the cannon ball.

Question 3

Which will hit the ground first, the cannon ball dropped straight down or the one launched sideways?

They both hit at the same time – horizontal motion is independent of vertical free-fall.