# Pulling a block

whizbang21
I've been out 8 days and i missed this entire chapter, with a test on monday so im trying to get all caught up. but i dont know how to do any of this homework.

## Homework Statement

the mass is 3.80 kg, T = 16 N, and = 35 degrees. The surface has no friction. If x is horizontal and y is vertical...

i found tx=13.1 ty=9.2 and normal force=28 but i dont know if that has anything to do with what im trying to find out..

what is the net force of the block in the x direction, and in the y direction. the acceleration of the block. What will be the position of the block after 12 seconds if it starts from a position 3 m from the left of the origin at a speed of -5 m/sec right? and what will be the velocity of the block at this time?

## Homework Equations

no clue or else i would have figured it out myself.

## The Attempt at a Solution

#### Attachments

• Pulling_at_angle.gif
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## Answers and Replies

Mentor
i found tx=13.1 ty=9.2 and normal force=28 but i dont know if that has anything to do with what im trying to find out..
Good. That has plenty to do with answering this problem.

what is the net force of the block in the x direction, and in the y direction.
Start here. What forces act on the block? What are the components? (You've already solved most of this.) Add them up to get the net force. Give it a shot.

whizbang21
i found net-x but net-y im having trouble with, i've tried adding the ty and the normal force together and also subtracting them, it didn't work of course but im not sure if im doing it wrong or im getting screwed by significant figures. im kind of just stumbling around like a blind man as this is the first problem ive done this entire chapter and i havent received any help from my teacher.

Mentor
The net force in the y-direction should be easy to answer without any calculation. Hint: You used it to figure out the normal force, whether you realized it or not. (There are three forces contributing to the net force.)

whizbang21
your cryptic answers would probably be helpful if i had a textbook and at least 1 day in class, rather than learning everything from google and trial and error.

Mentor
your cryptic answers would probably be helpful if i had a textbook and at least 1 day in class, rather than learning everything from google and trial and error.
You figured out the normal force somehow. How did you do it?

whizbang21