What Angles Affect the Vector Components of a Weight on an Inclined Plane?

AI Thread Summary
The discussion focuses on the vector components of a weight on a frictionless inclined plane. It addresses three key angles: where the components are equal, where the parallel component is zero, and where the parallel component equals the weight. The solution indicates that the components are equal at 45 degrees, the parallel component is zero at 0 degrees, and they equal the weight at 90 degrees. The initial uncertainty about the approach was resolved through drawing and applying trigonometric functions. Understanding these angles is crucial for analyzing forces on inclined planes in physics.
dandy9
Messages
27
Reaction score
0

Homework Statement


The weight of a book sliding down a frictionless inclined plane can be broken into two vector components: one acting parallel to the plane, and the other acting perpendicular to the plane.
(a) At what angle is the components equal?
(b) At what angle is the component parallel to the plane equal to zero?
(c) At what angle is the component parallel to the plane equal to the weight?

Homework Equations


Fnet = ma

The Attempt at a Solution


I'm not really sure how to approach this.
My guess for (a) is 45 just because it sounds reasonable that the components would be equal at the middle of 0 to 90 degrees.
 
Physics news on Phys.org
try to imagine a book on a inclined plane inclined at say angle a...
If weight is mg, component of weight perpendicular to incline is ..?
what is the component of weight parallal to incline?

draw figure and then you'll easily solve it
 
Thank you!

I got them all - thanks for getting me started! This is how I did it:
(a) cos and sin are equal at 45degrees
(b) the sin of 0 gives a component of 0.
(c) if the component and weight are equal then you take the inverse sin of 1 and get 90.
 
Very good.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Back
Top