Recently took a test and got one of the lowest scores I've ever gotten....theres no tutor avaliable and the prof isnt avaliable either....I'm trying to figure out the correct answers and how and which equations to use for each problem. I always have difficulty interpreting the questions and understanding them completely....and end up using incorrect equations and so forth....These are the questions I got completely wrong on the test and need help with.....(adsbygoogle = window.adsbygoogle || []).push({});

1.A ball is hit w/ a horizontal vector component of 15.0 m/s to the right and the vertical vector component of 20.0 m/s upward. What are these component velocities after 2.0s?

I first found the velocities for the horizontal and vertical using v= d/t....I got this problem wrong.

2.A car moving at 30.0 meters per second stops in 10.0 meters. How much time (in seconds) was required for the stop? Extra- What was the 'deceleration' as a factor of "g"?

I used t=d/v and got .333s and used that to find the acceleration and also got this problem wrong.

What tension (ie Force) must a 2.0 meter length of cord provide in order to whirl an attached 15.0 kg mass in a circular path with a tangential speed of 5.0 m/s? and can you perform this operation?

I used Fc= mv^2/r

= (15.0 kg)(5.0 m/s)^2

____________________

3.14

I am not sure how to tackle this problem.

A 50.0 kg object is lifted using 4900.0 J. How high is it lifted? and what maximum kinetic energy is possible if it falls?

I left this one blank..i was clueless

THX

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# Homework Help: Difficulty on some distance problemsneed help

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