Work, Work, Work
What is the SI unit for work?
A. Watts
B. Joules
C. Newtons
D. Meters
B. Joules
What is the SI unit for power?
A. Watts
B. Joules
C. Newtons
D. Meters
A. Watts
A simple machine that consists of two disks or cylinders, each one with a different radius.
A. Inclined Plane
B. Lever
C. Screw
D. Wheel & Axle
D. Wheel & Axle
What is the SI unit for energy?
A. Watts
B. Joules
C. Newtons
D. Meters
B. Joules
The highest point in a wave is known as the....
A. Trough
B. Wavelength
C. Crest
D. Amplitude
C. Crest
True or False:
Any part of a force that does NOT act in the direction of the motion does no work on an object.
ex. lifting a barbell directly over your head
TRUE
How much power is required to do 100 joules of work in 2 seconds?
A. 200 Watts
B. 50 Watts
C. 200 Joules
D. 50 Joules
B. 50 Watts
A wedge is made of two ____________________.
A wedge is made of two inclined planes.
____(a)____ _______ is the energy of motion, while ___(b)___ _______ is stored energy.
(a) KINETIC energy
(b) gravitational POTENTIAL energy
Which type of wave travels perpendicular?
A. Transverse ONLY
B. Longitudinal ONLY
C. Both Transverse and Longitudinal
A. Transverse ONLY
(must include correct unit for full credit)
You lift a box with a force of 7 N for a distance of 3 meters.
W = F x d
W = 7 x 3
W = 21 Joules (J)
How much power is required to do 200 joules of work in 4 seconds?
50 Watts
When the Effort is in the middle of a lever, what class of lever is it?
A. 1st
B. 2nd
C. 3rd
C. 3rd
F L E
1 2 3
When particles move faster what happens to Kinetic energy and what happens to Potential energy?
KE ____(a)_____, while PE ____(b)____.
When particles move faster what happens to Kinetic energy and what happens to Potential energy?
KE increases, while PE decreases.
What do waves carry?
ENERGY
You lift 5 boxes with a force of 2 Newtons PER box. You lift the boxes 3 meters each. How much work is being done?
You lift 5 boxes with a force of 2 Newtons PER box. You lift the boxes 3 meters each. How much work is being done?
F = 5 x 2
F = 10 N
W = F x d
W = 10 N x 3 m
W = 30 Joules (J)
You and your friend Bill Nye lift 5 boxes with a force of 2 Newtons PER box. You lift the boxes 3 meters each. Bill Nye lifts the boxes in 10 seconds while you lift the boxes in 30 seconds.
Who has more power and how much more power do they have?
You and your friend Bill Nye lift 5 boxes with a force of 2 Newtons PER box. You lift the boxes 3 meters each. Bill Nye lifts the boxes in 10 seconds while you lift the boxes in 30 seconds.
Who has more power and how much more power do they have?
P= W / t
You: 30 J / 30 s = 1 Watt of Power
Bill Nye = 30 J / 10 s = 3 Watts of Power
Bill Nye uses 2 more Watts of Power than you!
List a simple machine found in scissors.
1. lever
OR
2. wedge
1. What two things are kinetic energy dependent on?
a.
b.
2. What two things are potential energy dependent on?
a.
b.
1. What two things are kinetic energy dependent on?
a. MASS
b. SPEED
2. What two things are potential energy dependent on?
a. MASS
b. POSITION
Regarding sound, amplitude controls _____(a)_____, and frequency controls _____(b)______.
(a) volume
(b) pitch
You and your friend are playing Jenga. Each Jenga has a mass of 1 gram and you lift them with an acceleration of 2 m/s2. You pull/lift 5 Jenga pieces 0.5 meters before the Jenga tower falls. What is the amount of work being done?
Hints:
F= m x a
W = F x d
Force = 2 N PER Jenga
2 N x 5 Jenga = 10 N total
W= 10 N * 0.5m
W= 5 Joules
A new conveyor system at the local packaging plan will utilize a motor-powered mechanical arm to exert an average force of 890 N to push large crates a distance of 12 meters in 22 seconds. Determine the power output required of such a motor.
*must include correct unit for credit*
W = 890 x 12
= 10,680 Joules
Power = 10,680 J / 22 s
= 485. 45 Watts
Name the 6 types of simple machines and give an example of 3 of the 6.
1. Lever - broom
2. Pulley - compound pulley
3. Wheel & Axle - steering wheel
4. Inclined Plane - ramp
5. Wedge - axe
6. Screw - plastic water bottle lid
What is the difference between conduction, convection, and radiation?
**MUST have all three to gain credit**
conduction: heat transfer by touch
convection: transfer of heat by fluid
radiation: transfer of heat by waves
What is the unit for the frequency of waves?
Hertz