Animals live on land but return to the water to breed.
The sun is mostly made up of which gas?
On the following metric units which is the smallest
On the following elements which is the most common in the earth's crust?
Coral are animals that live in
Deep sea vents
Cold polar waters
All of the above
A rise in atmoshpheric temperature due to an increase in carbon dioxide, methane and other gases that trap heat in the atmoshpere is called____.
Green house effect
El niño phenomenon
Suppose that a river has a channel cross section of 25 square meters and a flow speed of 6 meters per second. What is its discharge rate?
6 m^3/ s
25 m^3/ s
150 m^3/ s
300 m^3/ s
Which of the following determines the development of soil in a particular place?
Presence of plant and animal life
The type of rock
All are factors of soil development
The [blank_start]ozone layer[blank_end] is the region of the atmoshpere which absorbs harmful UV radiation.
Troposphere is warmest near the Earth's surface because
Lightning strikes the surface which in turn heats the layer above.
The Earth's surface reradiates solar energy which heats the lower troposhere.
Radioactive elements in the Earth's crust heat atmosphere abovr the ground.
The air is most compressed there by the weight of the atmosphere.
Fog is a cloud with its base at or very near the ground. The formation of fog generally occurs after the ground has lost heat by
Evaporation is the process by which a liquid changes into gas. In this process, liquid water molecules become
Tiny drops of water
Molecules of water vapor
Separate atoms of water
Atoms of the hydrogen and oxygen
Thunderstorm is produce by a cumulonimbus cloud and is always accompanied by lightning and thunder. If you hear a clap of thunder a minute after seeing a flash of lightning, the distance between you and the lightning is about
Plant cells contain most of the same organelles and structures found in animal cells. The only difference is that plant cells have
A cell wall
An example of compound is
When matter is changed into another matter having different properties, the type of change is known as
Baking soda produces carbon dioxide when mixed with
The bubbling of softdrinks is due to
Air dissolved in the liquid
Carbon dioxide dissolved in liquid
Alcohol in the liquid
Sugar in the liquid
A gas which bacteria extract from air and change into a form which plant can use is [blank_start]nitrogen[blank_end].
Pressure is the pull or push exerted by a weight on a given unit of area. Since air has weight, it exerts pressure on all objects exposed to it.
Decreasing air pressure, air can be made to move from a [blank_start]high[blank_end] pressure region to a [blank_start]low[blank_end] pressure region.
Clouds are made up of
dust particles only
tiny droplets of water
partially evaporated water
winds are caused by
the motions of the earth
the waving of tree branches
the unequal heating of the earth's surface
The movement of the wind is always from
north to south
east to west
low pressure region to high pressure region
high pressure region to low pressure region
Density of a substance is its mass per unit volume.
A piece of brass has a mass of 16.0 g and a volume of 1.9 cm³, Find its density.
4.2 g/cm ³
8.4 g/cm ³
0.11875 cm ³
12.6 g/cm ³
Heat is the total kinetic energy of all the molecules of an object and its measured in Calories or
The measure of the average kinetic energy of molecules is known as
heat of evaporation
Which is true about light?
Light has the property of waves only.
Light is produced by excited atoms.
Light striking your eyes will not allow you to see.
Light energy cannot be measured.
The color of all objects depends on the light reflected from that color. Color is related to the frequency and ________.
wavelength of light waves
All electric currents are streams of moving electrons. The path followed by an electric current is called _____.
A series of circuit is a single pathway for all electrons in a circuit.
A parallel circuit has two or more branches for electrons.
If all Christmas lights go out when one bulb is burned out, the lights are connected in _______.
Acceleration is the rate of change of velocity per unit time.
A car accelerates uniformly from 15 kph to 45 kph in 10 seconds. The acceleration is [blank_start]3 km/hr-sec[blank_end] .
The distance covered by an object that starts from rest and accelerates uniformly depends upon the square of the time elapsed. d = Vi + (1/2) gt²
An object starts from rest and falls freely under the force of gravity for 5 seconds. What distance has it fallen during this time?
The acceleration of a body is directly proportional to the net force acting on the body and is inversely proportional to its mass.
What force would your arm have to exert to a bowling ball with a mass of 5 kg down an alley with an acceleration of 10 m/sec²?
The product of the mass and the velocity of a body is called its momentum (momentum = mv).
A gun having a mass of 5 kg fires a 20 g bullet at a speed of 500 m/sec. Find the recoil velocity of the gun.
Work in a physical science is equal to the force times the displacement in the direction of the force.
(W = Force x displacement)
A crate is pushed 5 meters on a level floor. The frictional force is determined as 300 N. Calculate the work performed.
Potential energy or energy of position is the product if the weight if an object and the height to which the object is elevated.
A machine weighing 5000 N is raised onto the roof of a building 50 m high, The increase in potential energy is [blank_start]2.5 x 10^5 Joules[blank_end].
2.5 x 10^5 Joules
2.5 x 10^5 Newton
2.5 x 10^4 Joules
2.5 x 10^4 Newton
A rocket with a mass of 1000 kg is fired vertically upward with an initial velocity of 100 m/sec. Calculate its potential energy when it reaches the maximum height.
5 x 10 ^ 5 Joules
5 x 10 ^ 5 N-m
5 x 10 ^ 6 Joules
5 x 10 ^ 6 N-m
A substance that gives up hydrogen ions to water to form hydronium ions is called _____.
The radius of a gold atom is 144 picometer. Express this radius in centimeter.
1.44 x 10 ^ -5 cm
1.44 x 10 ^ -6 cm
1.44 x 10 ^ -7 cm
1.44 x 10 ^ -8 cm
It is the property of matter that is independent of its surrounding condition and position.
An example of a substance that cannot be further decomposed by ordinary chemical means is ______.
A substance that can be further simplified may either be
a mixture or an atom
a mixture of a compound
an element or a mixture
an element or a compound
An example of chemical change is the
burning of wood
breaking of a glass bottle
melting of an ice cube
sawing of a piece of wood
Chemical reaction may involve all of the following except
separation of the molecules in a mixture
breaking down of compounds into elements
combination of atoms of elements to form a molecule
reaction of a compound and an element to form a new compound and a new element
Carbon - 14 has a half-life of approximately [blank_start]5600 years[blank_end]
Which of the following has 4 significant figures?
An orbital can NEVER be occupied by
A positively-charged ion has:
more protons than electrons
more electrons than protons
an equal number of neutrons and electrons
an equal number of protons and electrons
Sound is a form of energy produced by the vibration of matter. When an object produces sound, the vibration travels through space as