Science 4th Grading 2nd Sem
Two carts of the same mass m and speed v are approaching each other. The total momentum of the system is ______________.
0
A man on top of a hill throws a ball with a horizontal speed of 9 m/s. The horizontal distance traveled after 3 seconds is _______.
27 m
If the direction of one of the carts in item 6 is reversed, the total momentum of the system would be ________________.
2mv
How will you classify the stuntman in this picture?
A freely falling body
A stunt car jumps from the top of a truck to the top of another as shown in the picture on the opening page of this chapter. How will you classify the car based on its motion while in the air?
A projectile
What kind of energy are you taking in when eating food?
Chemical
Mechanical Energy windmill is transferred to _____ Energy.
Electrical
What is it called when one form of energy is changed to another form?
Energy transformation
It generates electricity from the thermal energy from the earth's interior.
Geothermal power plant
Which of the following is the SI unit of momentum?
Kg.m/s
When you eat pizza, Chemical Energy is transferred to _____ Energy.
Mechanical
Shaft work is fed to _____________ in getting an electrical output.
Motor
Which is the only fuel better than coal for use?
Natural gas
Which of the following refers to sources of energy that cannot be replenished by themselves for a short period of time?
Nonrenewable energy sources
What motion is illustrated by a ball thrown horizontally?
Projectile motion
As a microwave oven is operated, electrical energy is transformed into all of the following types of energy EXCEPT —
Solar
It generates electricity from the radiant energy of the sun.
Solar power plant
The cheapest and the simplest plant in operation and maintenance is ____________.
Steam power plant
A mango falls off a tree. After 0.1s, it is moving at -0.93 m/s. What does the quantity -0.93 m/s imply?
The mango is falling downward.
Electrical Energy in an oven is transferred to _____ Energy.
Thermal
What can friction create?
Thermal energy
Why are transformers needed in transmitting electricity over long distances?
They step up and step down voltages, making transmission more efficient.
A body is thrown horizontally and another body is dropped simultaneously from the same height. Which of the following statement correctly describes the motion of the two bodies?
They will reach the ground at the same time.
The secondary sources of energy sources of energy are _____________.
Wood, animal waste
When is kinetic energy GREATEST on a roller coaster?
at the bottom of the highest hill
what type of energy is stored in a battery?
chemical
Which energy conversion is taking place when you put gasoline in a car?
chemical -> mechanical
What type of energy is stored inside a battery?
chemical potential energy
According to the Law of Conservation of Energy, energy cannot be _________ or ____________.
created, destroyed
Which of the following quantities appears in the electric bill?
electric power
Solar Energy in the solar panels is transferred to _____ Energy.
electrical
What is the energy of moving electrons?
electrical
What kind of energy output is obtained from a steam power plant?
electricity
What is energy changing from one form to another?
energy transformation
Which of these is a conventional source of energy?
fossil fuels
It measures the electrical energy consumed.
galvanometer
In fuel cell, chemical energy is converted into ____________ energy.
heat
The main source of production of biogas is _____________________.
human waste, wet cow dung, wet livestock waste
It generates electricity from gravitational potential energy.
hydroelectric power plant
What is energy?
is the ability to do work or cause a change is all the movement in the universe cannot be created or destroyed
What is energy in motion?
kinetic
The alternator is used in power plants which converts energy from ____________.
mechanical into electrical
It generates electricity from the fission of uranium atoms.
nuclear power plant
Which type of motion is a combination of a straight line motion and a free fall?
projectile
The principle of conservation of momentum is equivalent to stating that the total momentum of an isolated system __________________.
remains the same
What is mechanical energy?
sum of kinetic and potential energy
Any energy conversion will always result in what form of energy?
thermal
The curved path of a projectile is called its ______________.
trajectory
Which is the horizontal distance traveled by a projectile?
width
The primary sources of energy are _______________.
wind, biomass, geothermal
