Physics Semestral Assesment 1 – Grade 8

Number : 1

A car travels 100 km. The journey takes two hours. The highest speed of the car is 80 km/h, and the lowest speed is 40 km/h. What is the average speed for the journey ? in km/h.

A.   40

B.   50

C.   60

D.  120

 

Number : 2

A ball rolls down a ramp. The time takes to move from X to y is measured. Which other quantity must be measured in order to calculate the average speed of the ball between point X and Y ?

 

A.   Distance between X and Y

B.   Angle of slope

C.   Diameter of ball

D.  Height of ramp

 

Number : 3

A cup contains hot liquid. Some of the liquid evaporates. What happens to the mass and what happens to the weight of the liquid in the cup.

	Mass	Weight
A	Decreases	Decreases
B	Decreases	Stay the same
C	Stay the same	Decreases
D	Stay the same	Stay the same

 

Number : 4

Which property of an object cannot be changed by applying forces?

A.   Speed                             C. Shape

B.   Direction of move             D. Mass

 

 

Number : 5

A ball is dropped in an evacuated tube A series of photographs is taken at equal time intervals from the time of release. Another ball of the same size but twice the mass is also dropped in the same evacuated tube and photographed. Which diagram shows the motion of the heavier ball ?

A.   A               B. B               C. C               D. D

Number : 6

A ball is dropped from table – top. Air resistance may be ignored. Which row describes the velocity and the acceleration of the ball at point X ?

 

 

	Acceleration	Velocity
A	Constant	Constant
B	Constant	Increasing
C	Increasing	Constant
D	Increasing	Increasing

 

Number : 7

Which row contains two correct statements about the mass and the weight of an object ?

 

	Mass of the object	Weight of the object
A	Is measured using a measuring cylinder	Is measured using a balance
B	Is measured in Newton	Is measured in kilograms
C	Is the same everywhere	Can vary from place to place
D	Is the gravitational force exerted on the object	Is the amount of matter in the object

 

Number : 8

The diagram shows the speed – time graph for a car.

 

Which area represents the distance travelled while the car is accelerating ?

A.   X + Y

B.   Y – x

C.   X

D.  Y

 

Number : 9

An astronaut in a space station orbits above the Earth. In the space station, the acceleration due to gravity is 7.5 m/s². On Earth, the acceleration due to gravity is 10 m/s². Which statement about the astronaut’s mass and weight in the space station is correct ?

 

	Mass of astronaut	Weight of astronaut
A	Lower than on Earth	Less than on Earth
B	Lower than on Earth	Greater than on Earth
C	Same as on Earth	Less than on Earth
D	Same as on Earth	Greater than on Earth

 

Number : 10

A steel ball is dropped from the top floor of a building. Air resistance can be ignored. Which statement describes the motion of the ball ?

A.   The ball falls with constant speed

B.   The ball falls with constant acceleration

C.   The ball falls with increasing acceleration

D.  The ball falls with increasing speed

 

Number : 11

A car travels along straight road. The speed – time graph for this journey is shown. During which labelled part of the journey is the resultant force on the car zero ?

 

Number : 12

In which situation is no resultant force needed ?

A.   A car changing direction at a steady speed

B.   A car moving in a straight line at a steady speed

C.   A car speeding up

D.  A car slowing down

 

Number : 13

Which distance / time graph represents the motion of an object moving at constant speed ?

Number : 14

Which statement about the masses and weights of objects on the Earth is correct ?

A.   Heavy objects always have more mass than light ones

B.   A balance can only be used to compare weights, not masses

C.   Mass is a force but weight is not

D.  Large objects always have more mass than small ones

 

Number : 15

A car travels forwards along a straight horizontal road. Only the horizontal forces acting on it are shown.

 

The length of each arrow represents the size of each force. How do these forces affect the motion of the car.

A.   The car’s forward speed increases

B.   The car moves backwards

C.   The car slows down

D.  The car moves at constant speed

 

Number : 16

Hukum Inersia disebut juga dengan hukum Newton ke - …

A.   I

B.   II

C.   III

D.  IV

 

Number : 17

Mengapada ban berbentuk bulat dapat mengurangi gaya gesekan

A.   Karena ban terbuat dari karet

B.   Karena lebih nyaman

C.   Karena permukaan ban yang bersentuhan dengan aspal lebih

    sedikit

D.  Karena permukaan ban tidak rata

 

Number : 18

Kombinasi gaya yang berupa dorongan dan tarikan secara bersamaan terdapat pada kegiatan …

A.   Menyapu lantai

B.   Merobek kertas

C.   Memasak

D.  Menulis

 

Number : 19

Benda akan bergerak jika gaya yang bekerja pada benda melebihi …

A.   Gaya gesekan statis                 C. massa benda

B.   Gaya gesekan kinetis               D. volume benda

 

Number : 20

Berikut yang bukan merupakan keuntungan dari adanya gaya gesekan adalah …

A.   Dapat menulis

B.   Dapat berjalan

C.   Dapat berhenti

D.  Dapat berputar

 

 

 

Kunci

 

No.	Kunci		No.	Kunci
1	B		11	B
2	A		12	B
3	A		13	D
4	D		14	A
5	B		15	C
6	B		16	A
7	C		17	C
8	C		18	B
9	C		19	A
10	B		20	D