Answer:
C) 40 N/m
Explanation:
If we ASSUME that the spring is un-stretched at the zero cm position
k = F/Δx = 10/0.25 = 40 N/m
Answer: Hello!
Lewis is travelling at 165 mph, which means miles per hour, this says that he does 165 miles in one hour.
We want to know how much time takes to cover 16 miles.
this can be calculated as the quotient of the distance and the velocity; this is:

if we want to write this in minutes, then:
we know that one hour has 60 minutes, then 0.096 hours has:
0.096h*60mins/1h = 5.8 minutes.
then Lewis needs 5.8 minutes in order to cover 16 miles if his speed is 156 miles per hour.
Answer:
Explanation:
This is a recoil problem, which is just another application of the Law of Momentum Conservation. The equation for us is:
which, in words, is
The momentum of the astronaut plus the momentum of the piece of equipment before the equipment is thrown has to be equal to the momentum of all that same stuff after the equipment is thrown. Filling in:
![[(90.0)(0)+(.50)(0)]_b=[(90.0)(v)+(.50)(-4.0)]_a](https://tex.z-dn.net/?f=%5B%2890.0%29%280%29%2B%28.50%29%280%29%5D_b%3D%5B%2890.0%29%28v%29%2B%28.50%29%28-4.0%29%5D_a)
Obviously, on the left side of the equation, nothing is moving so the whole left side equals 0. Doing the math on the right and paying specific attention to the sig fig's here (notice, I added a 0 after the 4 in the velocity value so our sig fig's are 2 instead of just 1. 1 is useless in most applications).
0 = 90.0v - 2.0 and
2.0 = 90.0v so
v = .022 m/s This is the rate at which he is moving TOWARDS the ship (negative was moving away from the ship, as indicated by the - in the problem). Now we can use the d = rt equation to find out how long this process will take him if he wants to reach his ship before he dies.
12 = .022t and
t = 550 seconds, which is the same thing as 9.2 minutes
Answer:
1.40625 kg-m^2
Explanation:
Supposing we have to calculate rotational moment of inertia
Given:
Mass of the ball m= 2.50 kg
Length of the rod, L= 0.78 m
The system rotates in a horizontal circle about the other end of the rod
The constant angular velocity of the system, ω= 5010 rev/min
The rotational inertia of system is equal to rotational inertia of the the ball about other end of the rod because the rod is mass-less

=1.40625 kg-m^2
m= mass of the ball and L= length of the ball
Answer:
1850 N
Explanation:
The formula for friction force between the load and plane is given as ;
F= μ*N
N = mg cos θ
To find θ, which is the angle the inclined plane makes with the ground at the height of 1.5 m
Sin θ = 1.5/4.5
Sin θ = 0.3333
Sin⁻{0.3333} = 19.50°
θ = 19.50°
Finding N , where m= 500 N , and g= 9.81
N = mg cos θ
N= 500 * 9.81 * cos 19.50°
N= 4624 N
Coefficient of kinetic friction is calculated as;
μ=F/W
μ = 200/500 = 0.4
The magnitude of kinetic friction is given as;
Fk= μ * N
Fk = 0.4 * 4624
Fk= 1850 N