A tower crane (construction crane) belongs to:
rotary machines
simple machines
Class 1 simple levers
compound machines
A cargo cart accelerates less when it is:
empty with a greater applied force
loaded with a greater applied force
empty with the same applied force
heavily loaded with the same applied force
When balanced forces act on a stationary body, the body:
stops suddenly
accelerates
remains stationary
moves slowly
Two forces of 20 N act on a body in the same direction. The resultant force equals:
20 N
10 N
40 N
0 N
The bicep muscle (forearm) in the human body represents a:
Class 2 lever
Class 1 lever
not a lever at all
Class 3 lever
Increasing the length of the effort arm in a lever leads to:
automatically reducing the length of the load arm
increasing the amount of force needed to lift the load
having no effect on the required lifting force
reducing the force needed to lift the same load
A lever is in equilibrium when:
the effort moment is greater than the load moment
the effort arm equals the load arm
the effort equals the load in magnitude
effort × effort arm = load × load arm
What is the magnitude of the resultant force needed to move a car of mass 1,200 kg with an acceleration of 3 m/s²?
3,600 N
3,000 N
1,200 N
400 N
Pliers are an example of a:
The seat belt in a car works according to Newton's:
Second Law
Law of Universal Gravitation
Third Law
First Law
In a perfectly inelastic collision between a moving body and a stationary one of equal mass, the speed of each after the collision is:
the same speed as the moving body before the collision
zero immediately after the collision occurs
half the speed of the moving body before the collision
double the speed of the moving body before collision
In an air-hockey experiment, the puck continues to move a long distance because:
friction between the puck and the table is reduced by the air layer
the applied force increases steadily with time
there is no gravity acting on the puck
the puck is very heavy and has high inertia
If a force F acts on a body of mass m and gives it an acceleration a, what happens to the acceleration if the force is doubled while the mass stays the same?
2a
a
4a
a/2
Standing on tiptoes represents a:
Objects with greater mass have ______ inertia:
the same inertia as smaller objects
mass has no relation to inertia at all
greater
smaller inertia than lighter objects
A lever provides mechanical advantage (M.A. > 1) when:
there is no relation between the arms and MA
both the effort arm and load arm are equal
the effort arm is longer than the load arm
the load arm is longer than the effort arm
The SI unit of force is:
J
N
kg
m/s²
The Flyboard (water-propelled hoverboard) works on the principle of:
universal gravitation
action and reaction
balanced forces
inertia
In a Class 2 lever, the fulcrum is located:
between the effort and the load, with the effort between them
outside the lever and does not affect motion
at one end of the lever, with the load between the fulcrum and the effort
always in the middle between effort and load
Newton's Second Law is expressed by the equation:
F = a / m
F = m + a
F = m × a
F = m / a
Cruise Control in cars makes the forces acting on the car:
multiplied
balanced
zero
unbalanced
A moving body collides with a stationary one of equal mass. The moving body stops and the stationary one moves at the same speed. This collision is:
semi-elastic
elastic
has no type
inelastic
A Class 2 lever always provides mechanical advantage because:
the fulcrum is located exactly in the middle
the effort arm is always longer than the load arm
the effort force and load force are always equal
the load arm is always longer than the effort arm
A uniform metal rod AB, length 60 cm and weight 5 N, rotates about point A. A newton meter is attached at end B to balance the rod horizontally. What is the newton meter reading?
8 N
5 N
2.5 N
In a Class 1 lever, the fulcrum is located:
outside the lever completely
at the point where the effort is applied
at the point where the load is applied
between the effort and the load
The human head represents a:
When unbalanced forces act on a stationary body, the body moves in:
a completely random direction with no pattern
it does not move at all from its position
the direction opposite to the force
the direction of the resultant force
The law that explains how a rocket is launched in the direction opposite to the ejected burning gases is:
Newton's Second Law
Newton's Third Law
The Law of Universal Gravitation
Newton's First Law
Newton's First Law is also known as:
The law of gravitation
The law of inertia
The law of action and reaction
The law of acceleration
Inertia is the property of bodies to:
resist any change in their state of motion
generate their own force
change their speed quickly
stop automatically
Two forces of 30 N and 20 N act on a body along the same line of action in opposite directions. The resultant force equals:
50 N
25 N
A weight of 20 N is hung 15 cm to the right of the fulcrum, and a weight of 30 N is hung to the left at distance x. The value of x equals:
20 cm
10 cm
15 cm
30 cm
A drone (unmanned aerial vehicle) moves upward because:
the drone is lighter than the surrounding air
gravity is reversed and points upward instead
the motors pull air upward in a direct manner
the downward push of air is matched by the air pushing the drone upward
Which of the objects X, Y, and Z below is subject to a non-zero resultant force?
X, Y, and Z
Z and Y only
Y only
X only
A lever is a:
rod with complex internal gears and teeth
rigid rod that rotates about a fixed point
flexible rod that bends easily under heavy load
movable rod that works freely without any fulcrum
Which of the following objects has the greatest inertia?
A car of mass 1,000 kg moving at 50 m/s
A locomotive of mass 2,000 kg moving at 30 m/s
A runner of mass 70 kg moving at 30 m/s
A ball of mass 0.1 kg moving at 50 m/s
A wheelbarrow is an example of a:
Class 4 lever
If a car has a mass of 1,000 kg and a driving force of 1,300 N acts on it (ignoring other forces), its acceleration equals:
13 m/s²
130 m/s²
1.3 m/s²
0.13 m/s²
A Class 3 lever does not provide mechanical advantage, but it:
increases speed and extends the range of motion
reduces the total distance that the load travels
increases the amount of applied force significantly
only changes the direction of the applied force
The mechanical advantage (M.A.) of a lever equals:
effort × load
effort + load
effort ÷ load
load ÷ effort
A resultant force of 1 N acts on a body of mass 1 kg. The acceleration produced is:
0.1 m/s²
1 m/s²
10 m/s²
100 m/s²
When the mass of a moving body increases while the applied force remains constant, its acceleration:
becomes zero
increases
decreases
stays the same
A person jumps from the front of a small boat and the boat moves backward. This is explained by:
the law of gravitation
Simple machines are tools that:
generate mechanical energy directly from the surrounding air
multiply the total amount of energy in a closed system
facilitate work and reduce effort, or change the direction of force
work automatically without needing any external force
When the electric current to a rotating fan is cut off, its blades continue to spin for a while due to
gravity
air friction
magnetism
Passengers in a bus lurching forward when it brakes suddenly is explained by:
According to Newton's Third Law, the action force and reaction force act on:
no at all physical body
the same exact body
more than two different bodies
two different bodies
A tennis racket is an example of a:
An airbag reduces the impact force on the driver by:
increasing the driver's speed just before impact
reducing the driver's mass during the collision
increasing the time of velocity change
stopping the car immediately upon collision
A lemon squeezer is an example of a: