Download 6) Solve the following problems

Egyptian Language School
Science Department
Physics 1st Sec.
Physics Final Revision for first sec .
1. Match the following physical quantities with its unit:
Physical quantity
1. Displacement.
2. Temperature.
3. Work.
4. Gravitational constant.
5. Density.
6. Force.
7. Acceleration.
8. Mass.
9. Kinetic energy.
4) compare between:
unit
a. Kelvin.
b. Joule.
c. Kg.m/𝑠𝑒𝑐 2
d. N.m2.Kg-2
e. Kg/m3
f. N
g. m/s2
h. meter
i. Kg
j. N.m
a. Mass & weight.
c. scalar & vector quantities.
6) Solve the following problems:
1. A body is projected upwards; it reaches the max height after 3 sec. find max height
reached.
2. A body moves by a velocity 5ms-1 with uniform acc 1.5 ms-2, find its velocity after
covering 200m.
3. Calculate the gravitational force between two bodies of masses 5000kg and 2000kg
separated by a distance of 0.5m,if the gravitational constant is 4.67×10-11N.m2/kg2.
4) a body of mass 2 kg moves in a circular path, its radius 2 m with velocity 12m/s calculate
a. the centripetal acceleration
b. the centripetal force
1) Write the scientific term for each of the following:
1. The body keeps its state of rest or motion in a straight line with uniform velocity unless any
external forces acting on it ………………………..
2. The tendency of a body to its state of rest or motion in a straight line with uniform velocity
……………………....…. .
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3. The product of the mass of a body times its acceleration …………………………….. .
4. For every action there is a reaction equals in magnitude and opposite in direction ....….……...
5. The motion of the body when it moves in a circular path with uniform velocity ………….………
6- The tendency of the body to maintain its state. ………………………………….
7. The product of the weight of the body and its vertical height from the surface of the
earth……………..…..
8-The product of the mass of a body and half its square velocity………….……………..
9. It is a comparison between two physical quantities of the same kind to know how many times
the first includes the second. ………………………………….
10. Physical Quantities that can’t be defined by other quantities. …………………………….
11. Physical Quantities that can be defined by other quantities. …………………………
12. I s the distance between two engraved marks at the end of rod made of platinum iridium alloy at
0oC………………………………………….
13. Is the mass of cylinder made of platinum iridium alloy of certain dimension kept at 0o C.
14. Is equal to 1/86400 of the average solar day.…………………………….
15.Is the difference between the actual value and the measured value.……………………….
16.Is the ratio between absolute error to the real value.…………………………..
17. Physical Quantities that can be fully defined by its magnitude only. ………………………..
18. Physical Quantities that can be fully defined by its magnitude and direction.……....……….
2-Match:
Physical Quantities
Unit in SI system
1-Length ( L )
1( )
a- o K
2-Mass
2( )
b- Sec
(M )
3-Time ( t )
3( ) c- Mol
4-Electric current intensity (I )
4( )
d- Candela
5-Absolute temp ( T )
5( )
e- Meter
6- Amount of material (n )
6( )
f- Ampere
7- Luminous intensity (I )
7( )
g- Kg
2
Complete the table
The physical
quantity
Area( A)
Density (ρ)
Speed (v)
Acceleration (a)
Force (F)
Relation to other
quantities
LxW
LxWxH
Mass/volume
Distance/ time
Dimensional formula
L x L = L2
L x L x L =L3
L / T = LT-1
LT-1 /T = LT-2
Mass x acceleration
unit
m3
Kg/m3
m/s2
N
Solve each of the following problems:2- An electric current has intensity (13mA) Express this intensity in
microampere.
3-A student measured the length of a pencil. It was found 13.9 cm, meanwhile its
actual length is 14cm. Estimate both the absolute error and relative error.
(0.1,0.7%)
Write the scientific term:1. An external influence that affects the object to change is state of motion or direction
(……………………..)
2. A static object keeps its state of rest, and a moving object keeps its state of motion at
uniform velocity in a straight line unless acted upon by a resultant
force(……………………….)
3. The tendency of an object to keep either its state of rest or its state of motion at its original
velocity uniformly in a straight line (………………………)
4. Objects resist changing their static or dynamic state (……………………)
5. When a resultant force affects an object, the object acquires an acceleration which is
directly proportional to the resultant force and inversely proportional to the object's mass
(……………………….)
6. The resistance of an object of mass 1 kg accelerates it at 1m/s2 (………………………...)
7. The force of gravity acting on the body towards the earth's center (……………………….)
8. For every action there is a reaction equal in magnitude and opposite in direction
(……………………)
9. When an object acts on another object by a force, the second object reacts with an equal
force on the first object in a direction opposite to that of the action(……………………..)
2- Choose the correct answer:
1. According to the Newton's first law, the body moves with ………… velocity unless any
external forces acting on it.
a. uniform
b. vanished
c. Non-uniform
2. The inertia of a body increase by increasing its …………
a. volume
b. Mass
c. displacement
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d. density
d. Increasing
3. The inertia of a body is:
a- The tendency of the body to maintain its shape and volume constant.
b- The tendency of the body to maintain its mass and volume constant.
c- The tendency of the body to maintain its state of rest or uniform motion
d- The tendency of the body to maintain its density.
4. The law of inertia is:
a. The Newton 1st law
b. The Newton 2nd law
c. The Newton 3rd law
d. Coulombs law
5. Which of the following is NOT a vector quantity?
A. momentum
b. Velocity c. acceleration.
d. Speed
6. The Newton second law is:
a- The body maintains its state of rest or motion in a straight line with uniform velocity
unless acted upon by a net force.
b- The net force = mass × acceleration
c- For every action there is an equal and opposite reaction
d- The law of inertia
7- Force is measured by a (N)
a-
Two pan balance
b-ammeter
c- spring balance
d-ruler
8- When the direction of acceleration is opposite to the direction of velocity, the
a- resultant force decreases
b- object velocity increases
c- Object velocity is unchanged
d -object velocity decreases
9- When the resultant force acting upon a moving car is zero, the car
a- moves at positive acceleration
b- moves at negative acceleration
c- Moves at uniform velocity
d- stops its motion
10- Newton's first law is known as the law of
a- reaction
b- mass conservation
c- inertia
d- energy conservation
12- The resultant force acting on an object=
b- mass x √velocity
a- mass x velocity
c- mass x rate of change of velocity
d- 1/2 mass x velocity 2
13-A wooden block of mass 2 kg is moving along a horizontal plane when affected by a force
of 6 N. if the frictional force is 2 N, the acceleration of the motion equals
a- 6m/s2 b-2m/s2
c- −3m/s2 d- −4m/s2
14-If the mass of a body is decreased to half and the acting force is reduced to quarter, then the
acceleration of its motion
A-Remains constant
c- Decreases to its half
b- Increases to its double
d- Increases four times
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15-If the acting force of a body is doubled and its mass decreased to half, the acceleration of its
motion become
a- a
b- 2 a
c- 3 a
d-4 a
8- Newton's third law is known as the law of
aInertia
b- Reaction c- Universal gravitation
d- Coulomb's
16- The mathematical formula that expresses Newton's third law is
a- F1 = −F2
c- ∑ F ≠ 0
b- F=ma
d- ∑F=0
3) Define the following terms:
a- Force
f- Mass
b- Newton's first
c- Inertia d- Newton's second law e- The Newton
g- Weight
h- Newton's third law
4) Solve the following problems:
1- Find the required force to accelerate a mass of 10 kg moving in a straight line, changing its
velocity from 54 km/h to 108 km/h during 10 s
2 A car of mass 1200 kg moved from rest under the effect of force 600 N. Find:
a- The acceleration by which the car moved
b- The car’s velocity after 25 s
c- The distance covered by the car
3- A static object of mass 20 kg is affected by a force 30 N. Find
a- The acceleration acquired by the object
b- The time taken by the object to cover a distance of 75 m
4- Find the force that affects on an object of mass 30 kg to:
a- Accelerate it at 3 m/s2
b- Speed it up from rest to 8m/s in 6 s
5- A car was moving at velocity 20 m/s in a straight road. The driver applied the brakes to
decelerate the car at 5 m/s2 Find:
a- The time taken for the car to stop and the distance required
b- The type of force that slowed the car down and the direction of its action
c- The magnitude of the force that stopped the car if its mass is 600 kg
6- A vehicle of mass 750 kg , moves in a circular path of diameter 80m if the centripetal force
on the vehicle 7500N, calculate the velocity of the vehicle
7-10- A car of mass 1 tone starts motion from rest with uniform acceleration of 2 m / s2.
Find its kinetic energy: Before it starts motion
Good Luck
a- After 10 sec.
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