Answer:
1.40 N
Explanation:
The magnitude of the frictional force is given by:
![F=\mu N](https://tex.z-dn.net/?f=F%3D%5Cmu%20N)
where
is the coefficient of friction
N is the magnitude of the normal reaction
The coefficient of friction for this problem is
. The magnitude of the normal reaction is equal to the combined weight of the boy and the sled, because the surface is horizontal, so
![N=65 N+52 N=117 N](https://tex.z-dn.net/?f=N%3D65%20N%2B52%20N%3D117%20N)
Therefore, the frictional force is
![F=\mu N=(0.012)(117 N)=1.40 N](https://tex.z-dn.net/?f=F%3D%5Cmu%20N%3D%280.012%29%28117%20N%29%3D1.40%20N)
For a lens, the following sign convention is generally used:
- f (the focal length) is positive for a converging lens and negative for a diverging lens
-
![d_o](https://tex.z-dn.net/?f=d_o)
(the distance of the object from the lens) is positive if the object is in front of the lens and negative if it is behind the lens
-
![d_i](https://tex.z-dn.net/?f=d_i)
(distance of the image from the lens) is positive if the image is behind the lens (real image) and negative if the image is in front of the lens (virtual image)
Therefore, the correct option is
<span>A. +di
</span>which mens that the image is real and located behind the lens.
Answer:
D
Explanation:
F = G m1 m2 / r^2 now double r
F = G m1m1/ (2r)^2
F = 1/4 G m1m2/r^2 <===== this is 1/4 of the original
Answer:
0.5 kg
Explanation:
» <u>Concepts</u>
Newton's second law, the Law of Acceleration, states that F = ma, where F = Force in Newtons, m = mass in kg, and a = acceleration in m/s^2.
» <u>Application</u>
We are asked to find the mass of the ball using the equation F = ma. We're also given the force and acceleration, so the equation looks like 5 = 10(m).
» <u>Solution</u>
Step 1: Divide both sides by 10.
Thus, the mass of the ball is 0.5 kg.
it's caused by a pressure that is large on the button of an object that it is on the top of an object submerged in a liquid.
Explanation:
This is why object appear to weigh less when immersed in a liquid. If the upthrust is greater than the weight of the object, the object will rise up through the liquid.