Using the Pythagorean’s theorem to find the resultant, we find 5’2 +3’2=x’2
X=square root of 34=5.8unitd
1) 3 miles/Hour
The speed is defined as the distance covered divided by the time taken:
where
d = 1.5 mi is the distance
t = 0.5 h is the time taken
Substituting,
2) 1.34 m/s south
Velocity, instead, is a vector, so it has both a magnitude and a direction. We have:
is the displacement in meters
is the time taken in seconds
Substituting,
And the direction of the velocity is the same as the displacement, so it is south.
Answer:
c) is negative
Explanation:
As we know that work done by a force is the product of force and displacement vector.
W= F.d
F= Force
d= displacement
The work done by friction force always negative because it try to oppose the motion and act opposite to the direction of displacement.So the work done by air resistance is negative.
c) is negative
Kinetic energy = (1/2) (mass) (speed)²
= (1/2) (1.4 kg) (22.5 m/s)²
= (0.7 kg) (506.25 m²/s² )
= 354.375 kg-m²/s² = 354.375 joules .
This is just the kinetic energy associated with a 1.4-kg glob of
mass sailing through space at 22.5 m/s. In the case of a frisbee,
it's also spinning, and there's some additional kinetic energy stored
in the spin.
