Answer:
C.The car appears to be moving 30 km/hr in the opposite direction of the bus.
Explanation:
There are two reference systems involved in this situation:
- Reference system S: this is the reference system where velocities are measured with respect to the ground. In this reference system, the car is parked, so its velocity is 
- Reference system S': this is the reference system moving with the bus. This reference system is moving with a velocity of 
with respect to the reference system S
Calling 
the velocity of the car in the reference system S', we have:
From which
and the negative sign means that a passanger in the bus observes the car moving in the opposite direction.
Answer;
30.6 m
Explanation;
All objects accelerate at the constant rate in the Earth's gravitational field. The gravitational acceleration, g = 9.8 m/s².
Distance traveled by an object falling down under a constant acceleration will be given the formula;
s = ut² + 1/2(gt²); but u the initial velocity is o
thus;
S =1/2(gt²)
= 0.5 × 9.81 × 2.5 ²
= 30.65
≈ 30.6 m
The compression curve would be theoretically given for a system of bodies in which the spring applies the force (Although in the same way the following process can be extrapolated to any system, depending on the type of Force to consider) For a spring mass system, the strength is given by Hooke's law as
Where,
K = Spring constant
x = Displacement
If we integrate based on distance we would have
This integral represents the area under the Force Curve based on each distance segment traveled.
This is the same formula that represents the elastic potential energy of a body. Therefore the correct answer is D.
Answer:
So A we cant sadly do because we cant draw. B is going to be kinetic. Thats because static friction means it stays in one place, for kinetic it means moving. So it will be 0.05 as the coefficient of the friction. Sadly, I cannot calculate C. You will have to use trigonemetry but I cannot fit that big an explanation.
Answer to A: the free body diagram would be the ski things inclined with gravity, friction, and air resistance. I except you know which directions
Answer to B: Kinetic friction is the answer.
Answer to C: Find on own, I cannot write super big explanations - use trigonometry.
Of the list, Ultraviolet waves have the shortest wavelength
