Answer:
5.22 Ns
Explanation:
A consequence of Newton's second law of motion is that:
Impulse = change in momentum
The initial momentum = (0.145 kg) × (15.0 m/s)
The final momentum = (0.145 kg) × (-21.0 m/s)
The final momentum has a negative sign because the ball returned in an opposite direction.
Change in momentum = final momentum - initial momentum = (0.145 kg) × (-21.0 m/s) - (0.145 kg) × (15.0 m/s)
= -0.145(21.0 + 15.0) kg m/s
= -0.145 × 36.0 kg m/s
= -5.22 kg m/s
The magnitude of the impulse is thus 5.22 Ns.
Unlike acceleration and velocity, speed does not need to specify the direction of motion. Speed is a scalar quality.
Answer:
Explained below
Explanation:
For the geometric meaning, I've attached a parallelogram showing two vectors a and B and also the angle between them as θ.
We can see that the two vectors are adjacent to each other.
So the magnitude of the product of the two vectors is simply the area of the parallelogram which is base x height. Thus;
Magnitude = |a| sin θ × |b|
This can be rewritten as;
|a|•|b| sin θ