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No matter how many times i do it, i seem to be doing something wrong :|

A wet bar of soap (150 g) slides without friction down a ramp (2.0 m) long inclined at 7.3degrees. How long does it take to reach the bottom? Neglect friction.

& How would this change if the soaps mass were 250 grams?

stated below>>

So i tried to calculate Fnet using sine.

since Fg=1.5kg*9.8=14.7N

Then i did, sin7.3=x(aka fnet) / 14.7

x = 12.5

Then: Fnet = ma

12.5=0.15a

a=83.3

then

d=vit+1/2at^2

2=0+1/2(83.3)t^2

2/(1/2*83.3)=t^2

Suqareroot(0.048)=t

t=0.219 or around there.

However the answer is 1.8 seconds?

Can anyone help me see what im going wrong?

Any help is much appreciated, thanks.

EDIT:::

Sorry, nevermind, turns out my calc was in radian mode -facepalm- Good grief.

## Homework Statement

A wet bar of soap (150 g) slides without friction down a ramp (2.0 m) long inclined at 7.3degrees. How long does it take to reach the bottom? Neglect friction.

& How would this change if the soaps mass were 250 grams?

## Homework Equations

stated below>>

## The Attempt at a Solution

So i tried to calculate Fnet using sine.

since Fg=1.5kg*9.8=14.7N

Then i did, sin7.3=x(aka fnet) / 14.7

x = 12.5

Then: Fnet = ma

12.5=0.15a

a=83.3

then

d=vit+1/2at^2

2=0+1/2(83.3)t^2

2/(1/2*83.3)=t^2

Suqareroot(0.048)=t

t=0.219 or around there.

However the answer is 1.8 seconds?

Can anyone help me see what im going wrong?

Any help is much appreciated, thanks.

EDIT:::

Sorry, nevermind, turns out my calc was in radian mode -facepalm- Good grief.

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