Answer:
We know that the force pulling the box in the positive x direction has a magnitude of m g sin 30 . Using Newtons Second Law, F = ma , we just need to solve for a :
ma=mgsin30
a=gsin30
=(10m/s2)(0.500)
=5m/s2
Answer:
The ground pushes back on your feet with equal force
Explanation:
When you walk across the ground and push on it with your feet, the ground pushes back on your feet with an equal and opposite force.
This interpretation and knowledge is gotten from Newton's third law of motion.
It states that "action and reaction force are equal and opposite in nature".
- The force applied to a body responds with an opposite force in the other direction.
- Therefore, the reaction force is of equal magnitude but directed in another direction.
The focal length of a magnifying glass is the distance between the focal point and optical centre of the magnifying glass.
<h3>Focal length</h3>
The focal length, f is the distance from a lens or mirror to the focal point, F.
This is the distance from a lens or mirror at which parallel light rays will meet for a converging lens or mirror or appear to diverge from for a diverging lens or mirror.
A magnifying glass is a converging lens which produces a enlarged, erect and virtual image when an object is placed between the focal point and optical centre.
A magnifying glass will bring to focus at a point sun rays which can cause the paper to catch fire if it is held in place for long.
This point at which the most concentrated ray of light is shining on the paper, is the focal point for that magnifying glass.
Therefore, the focal length of a magnifying glass is the distance between the focal point and optical centre of the magnifying glass.
Learn more about about focal length at: brainly.com/question/25779311
Answer:
c. 0.25km
Explanation:
v=f x wavelength
3000 = 12 x wavelength
wavelength = 3000/12 = 250m
250m to km
To convert m to km, we divide by 1000
250/1000 =0.25km
wavelength = 0.25km
