Science quizizz test
You do 20 J of work in pushing a crate up a ramp. If the output work from the inclined plane is 11 J, then what is the efficiency of the inclined plane?
55%
Alice kicks a soccer ball with a mass of 2.1 kg. The ball leaves the ground moving 30 meters per second. What is the kinetic energy of the soccer ball?
945 J
Which best describes the process of convection?
Convection is the primary way heat travels through liquids and gasses.
Which type of energy do objects elevated or raised to positions above the ground have?
potential energy
what is mechanical advantage?
the number of times a machine increases input force
Is it possible for an object to have no potential energy and have no kinetic energy?
yup
The temperature of an unknown piece of metal with a mass of 30.00 g changes from 25.0 °C to 35.0 °C when the metal absorbs 350.0 J of energy. What is the specific heat of the metal?
1.17 J/g°C
The specific heat of aluminum is 0.21 J/g°C. How much heat(Q) is released when a 10 g piece of aluminum foil is taken out of the oven and cools from 100° to 50°?
105J
The specific heat of aluminum is 0.21 J/g°C. How much heat(Q) is released when a 10 g piece of aluminum foil is taken out of the oven and cools from 100° to 50°?
12.82 °C
Calculate the heat needed to raise the temperature of 0.25 kg of aluminum 7°C (c=900 J/kg°C)
1575 J
If 150 Joules of work is needed to move a box 10 meters, what force was used?
15N
Calculate the potential energy of a car with a mass of 2,500 kg that is on a hill 100 meters above sea level.
2,450,000 J
You do 90 joules of work in 30 seconds. How much power have you generated?
3 watts
What is the mechanical advantage for a crate that weighs 950 N and is lifted with a pulley force of 250 N
3.8
The specific heat of aluminum is 0.9025 J/g°C. How much heat(Q) is released when a 10.0 g piece of aluminum foil is taken out of the oven and cools from 100.0° to 50.0°?
451 J
If a student uses 10 Newtons of Force to push a chair 5 meters, how much is work is being done?
50 J
The handle of a metal spoon warms up when it is placed in a hot bowl of soup because of ________.
Conduction
A student opens the top window and the bottom window in a hot room. What statement best describes the heat transfer occurring in the room?
Convection
Molecules with more kinetic energy move ———- than molecules with less kinetic energy
Faster
Explain the role friction plays in the conservation of energy
Friction causes some of the mechanical energy of an object to change into thermal energy. The total energy of a system—potential and kinetic plus any converted energy—remains constant.
What kind of energy transformation occur on a swing?
GPE to mechanical
What energy transformation takes place as a rock rolls down a hill?
Gravitational Potential Energy to Kinetic Energy
Why is there more thermal energy in an iceberg than in a pot of boiling water?
Icebergs contain many more molecules than pots of water
A high specific heat means...
It requires more energy to change temperature
Temperature of a material depends upon the average —————— of its particles
Kinetic energy
the average kinetic energy of the particles in iced tea is —————than the average kinetic energy of the particles in hot tea.
Lower
Kinetic energy is the energy of
Motion
In order for work to be done, what two things need to happen?
Object must move and must move in the direction of the force applied
What is the symbol for Thermal Energy?
Q
What is the equation to measure change in Thermal Energy?
Q = mc∆t
A group of friends gather around a fire to stay warm. This is an example of ________
Radiation
You get sunburned due to __________ from the sun.
Radiation
Machines can be made more efficient by ____________.
Reducing friction
The amount of energy required to raise the temperature 1ºC for every kilogram is called____?
Specific Heat
Which material is the best conductor of heat?
Steel
Thermal Energy depends upon the energy of the particles as well as the number of particles. Which would have more thermal energy, a small cube of Ice at zero Celsius or a large cube of ice at zero Celsius?
The large ice cube because it has more particles than the small ice cube
The total energy of all the particles in a sample of matter is called
Thermal energy
There are four cups of hot cocoa. The cup sizes are shown. The temperature of the cocoa in each cup is 25 degrees celsius. Which cup has the MOST thermal energy?
Trenta
Water has a specific heat of 4184 J/KgºC. Wood has a specific heat of 1760 J/KgºC. What material needs more energy to raise the temperature 1ºC
Water
What is the definition of CONDUCTION?
When heat transfers from objects that are touching.
A barefoot student steps on a hot concrete surface. Most of the heat transferred to the student's skin by this contact is by the process of-
conduction
Near the ceiling of a room the air is warmer. The warm air rises because of ________.
convection