Answer:
- The magnitude of the vector
is 107.76 m
Explanation:
To find the components of the vectors we can use:

where
is the magnitude of the vector, and θ is the angle over the positive x axis.
The negative x axis is displaced 180 ° over the positive x axis, so, we can take:






Now, we can perform vector addition. Taking two vectors, the vector addition is performed:

So, for our vectors:


To find the magnitude of this vector, we can use the Pythagorean Theorem



And this is the magnitude we are looking for.
Answer:
Explanation:
a )
We shall apply the concept of impulse .
Impulse = force x time = change in momentum
= 5 x 4 = 2 ( V - 3 ) , where V is final velocity of the object
20 = 2V - 6
V = 13 m /s
b )
Impulse applied = - 7 x 4 = - 28 kg m/s ( negative as direction of force is opposite motion )
If v be the final velocity
2 x 3 - 28 = 2 v ( initial momentum - change in momentum = final momentum )
- 22 = 2v
v = - 11 m /s
object will move with 11 m /s in opposite direction .
Fk = μK N
N = m a
N = 4 × a
N = 4a
Fk = μK N
17 = 5 × 4a
17 = 20 a
a = ¹⁷/₂₀ = 0.85 m/s²