Download Q1: Accleration is always in the direction: A. of the

Phys101
Term: 123
Online HW-Ch05-Lec01
Q1:
Accleration is always in the direction:
A. of the displacement
B. of the initial velocity
C. of the final velocity
D. of the net force
E. opposite to the final velocity
Ans:
Q2:
�⃗net = ma�⃗
D; F
�⃗ = 20𝚤̂ + 30𝚥̂ 𝑁.
The only force acting on a 5.0 kg object is F
magnitude of the acceleration of the object.
Find the
Ans:
a�⃗ =
1
1
�F⃗ = (20 ı̂ + 30 ȷ̂) = (4 ı̂ + 6 ȷ̂)m/s2
m
5
|a| = 7.2 m/s 2
Q3:
Ans:
While two forces act on it, a particle is to move at the constant velocity
�⃗ = (3ı̂ − 4ȷ̂)m/s One of the forces F = (2 ı̂ − 6 ȷ̂) N. What is the magnitude of the
v
other force?
�⃗2
�⃗ = constant ⇒ a�⃗ = 0 ⟹ �F⃗1 + �F⃗2 = 0 ⟹ �F⃗1 = −F
v
�⃗1 � = �F
�⃗2 � ⟹ |F2 | = �22 +62 = 6.3 N
⟹ �F
KFUPM-Physics Department
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