I was doing my hw but i am really stuck.(adsbygoogle = window.adsbygoogle || []).push({});

My teacher ain't that good he doesn't explain things very good.

If you can help plz help.

Thanks

1. a cyclist of mass 60kg riding up a hill which is inclined at 30 degress to the horizontal at a constant speed. the mass of the bicycle is 20kg.

a)calculate net force.

it's 0 cause he's goin at constant speed.

b)total friction=10n, what's the magnitude of the component of the weight of the system that is parrallel to the road surface?

I have no idea how to do it. i know u have to minus something by 10n.

in the diagram the weight pulling down is 800N.

c)claculate dricing force.

No idea but i think it would the answer in B divided by 100kg.

d)calc the magnitude of the normal reaction force on the bicycle system

again i have no idea.

if you know a site that explains how to do this very well iw would be happy to read it.

thanks

also another question

2)person skin downhil of 60kg(including skies) is moving down a slope inclined at 30 degrees with increasing speed. she is moving in a straight line down the slope.

a)direction of the net force on the skier.

it's down the slope.

b)Claculate magnitude of the component od the skiers weight that is parrallel to the slop.e

again i have no idea how to do it.

c)sum of friction is 8n, claculate net force on skier.

3)a ball of mass 0.5 kg is thrown vertically upwards.

a)calc velocity of the ball at the top of it's flight.

it's 0 cause it stops.

b)calc acceleration at the top of it's flight

it's 9.8 ms-1 cause gravity constant.

c) calculate net force on the ball at the top it's flight?

i couldn't do this 1, there is a net force cause it's accelerating.

and last 1

4)a car of mass 1200kg starats from rest on a horizontal road with a forward thrust of 10 000 N. the resistance to motion due to road and air resistance totals 2500N

1)calc net force.

it's 10000-2500

b)clac acceleration

it's 7500/1200

c)clac speed after 5 s.

this should be easy but i don't get it.

d)calculate the distance the car has travelled after 5 s

again it should be easy but it is annoying me.

If you can help me with these questions it would really help.

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# Homework Help: Physics Hw Help

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