<u>Answer:</u>
15.97 N force is tending to pull Rover forward
<u>Explanation:</u>
The woman pulls on the leash with a force of 20.0 N at an angle of 37° above the horizontal. The arrangement is shown in the given figure,
We nee to find the pulling force P. The 20.0 N force has two components, 20.0 cos 37 in horizontal direction and 20.0 sin 37 in vertical direction.
The horizontal component is equal to pulling force P, which will pull Rover forward/
So, P = 20.0 cos 37 = 15.97 N
15.97 N force is tending to pull Rover forward.
Answer:
The coefficient of rolling friction will be "0.011".
Explanation:
The given values are:
Initial speed,
then,
Distance,
s = 18.2 m
The acceleration of a bicycle will be:
⇒
On substituting the given values, we get
⇒
⇒
⇒
⇒
As we know,
⇒
and,
⇒
⇒
On substituting the values, we get
⇒
⇒
The propagation errors we can find the uncertainty of a given magnitude is the sum of the uncertainties of each magnitude.
Δm = ∑
Physical quantities are precise values of a variable, but all measurements have an uncertainty, in the case of direct measurements the uncertainty is equal to the precision of the given instrument.
When you have derived variables, that is, when measurements are made with different instruments, each with a different uncertainty, the way to find the uncertainty or error is used the propagation errors to use the variation of each parameter, keeping the others constant and taking the worst of the cases, all the errors add up.
If m is the calculated quantity, x_i the measured values and Δx_i the uncertainty of each value, the total uncertainty is
Δm = ∑ | dm / dx_i | Dx_i
for instance:
If the magnitude is a average of two magnitudes measured each with a different error
m =
Δm = | | Δx₁ + |
| Δx₂
= ½
= ½
Δm = Δx₁ + ½ Δx₂
Δm = Δx₁ + Δx₂
In conclusion, using the propagation errors we can find the uncertainty of a given quantity is the sum of the uncertainties of each measured quantity.
Learn more about propagation errors here: