hi guys i got a couple of questions can somebody help me out by telling me the steps of where to go about and i will try to get the answer on my own as i need to understand how to do these questions i will post what i know.(adsbygoogle = window.adsbygoogle || []).push({});

1. a train slows down as it turns, from 90 km/hr to 50 km/hr in 15seconds. the radius is 150m, calculate the acclereation the moment it reaches 50km/hr.

first of all i know the formula is a= v^2 / r

what i dont know is that i am given 90k/hr and 50 km/hr, time and a radius, im thinking maybe i dont use the a=v^2/r formula but perhaps v= u + at ?

2. there is a pictuer of a circle all i am given is radius is 2.50 m, outside the circle is a= 15 m/s^2 and insie the circle is an angle of 30degrees with a line going down. It wants me to calculate radial, tangential accerlearation along with the speed of the particle.

im thinking maybe the a=15 m/s^2 is the overall accleration and maybe use the components of sin30 and cos30 im lost please shed me some light ppl thanks

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# Homework Help: Rotational Motion - Help me out GUYS!

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