Answer:
The first law states that if the net force is zero, then the velocity of the object is constant.
Answer:
When there is wind it takes longer
Explanation:
With no wind, the round trip time is

When we have a constant wind speed w

comparing the reciprocal times;

This means that t1 is smaller than t2, ergo, it takes longer with wind
Answer:
49 N
Explanation:
In order to move the box at constant speed, the acceleration of the box must be zero (a=0): this means, according to Newton's second law,
F = ma
that the net force acting on the box, F, must be zero as well.
Here there are two forces acting on the box in the horizontal direction while it is moving:
- The force of push applied by the guy, F
- The frictional force, 
For an object moving on a flat surface, the frictional force is given by

where
is the coefficient of friction
m is the mass of the box
g is the acceleration of gravity
So the equation of the forces becomes

And substituting:

We find the force that must be applied by the guy:

Answer:
<em>13.54 tons</em>
Explanation:
Let f be the amount of fuel oxidizer needed
v be the speed
The relationship between them is inverse in nature i.e
f ∝ 1/v
f = k/v
If a rocket for use in deep space is to have the capability of boosting a total load (payload plus the rocket frame and engine) of 3.25 metric tons to a speed of 10,000 m/s, then f = 3.25 when v = 10,000
Substitute and get k
k = fv
k = 3.25 * 10,000
k = 32500
To get the amount of fuel oxidizer required to produce a speed of 2400m/s, we will find f when v = 2400m/s
Recall that f = k/v
f = 32500/2400
f = 13.54 metric tons
<em>Hence the fuel plus oxidizer that will be required is 13.54 tons</em>
Answer:
You are given that the mass of the clock M is 95 kg.
This is true whether the clock is in motion or not.
Fs is the frictional force required to keep the clock from moving.
Thus Fk = uk W = uk M g the force required to move clock at constant speed. (the kinetic frictional force)
uk = 560 N / 931 N = .644 since the weight of the clock is 931 N (95 * 9.8)
us is the frictional force requited to start the clock moving
us = static frictional force = 650 / 931 -= .698