Page 24 - Pra U STPM 2021 Penggal 1 - Physics

Physics Term 1 STPM Chapter 2 Kinematics

Important Formulae

1. Equations for motion with constant accelaration
1 1
v = u + at s = (u + v)t s = ut + at 2 2 2
v = u + 2as
2 2
2. Projectile
2
2
u sin θ 2
Maximum height, H =
2g
2
Range, R = u sin 2θ
g
Range is maximum when = 45°
At time = t, horizontal displacement, x = (u cos θ)t
1
vertical displacement, y = (u sin θ)t – gt 2
2

STPM PRACTICE 2

1. An object is projected vertically upwards from 3. An object starts from rest and its acceleration-
the top of a building of height 12.0 m with a time graph is as shown below.
–1
speed of 6.0 m s . What is the time taken by Acceleration / ms –2
the object to reach the ground?
[Acceleration of free fall is 10.0 m s .] 4
–2
A 1.06 s 2
B 2.00 s
0 Time / s
C 2.26 s 4 8 12 16
D 4.90 s –2

2. The displacement-time graph of a body is What is the maximum velocity of the object?
shown below. A 16 m s –1
B 22 m s –1
Displacement C 24 m s –1
D 26 m s
–1
Q
4. A vehicle decelerates uniformly from a speed
P R u. It takes a time t, and travels a distance
S d before stopping. Its speed, and distance
0 Time t
travelled after a time is given by
2
Which statement about the motion of the body Speed Distance travelled
is true? u d
A At P, the body is accelerating A 2 less than 2
B At Q, the speed of the body is zero B u more than d
C The velocities at P and R are the same 2 u d 2
D At S, the speed is constant C Less than less than
2
2
u d
D More than more than
2 2

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