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Like this? Ny=N Fky=0 Wy=-mgsin(21 Nx=0 Fkx=-mewk Wx=0 I did Fk=mewkN=.57*(mgsin(21)=.57*112.5=64.12 I did somthing wrong...again...but I don't know what...

To move a large crate across a rough floor, you push down on it at an angle of 21°. Find the force necessary to start the crate moving, given that the mass of the crate is m = 32 kg and the coefficient of static friction between the crate and the floor is 0.57. N=mg=(32)(9.81)= 313.92 *...

A shopper pushes a 7.5 kg shopping cart up a 13 degree incline. Find horizontal force needed to give the cart an acceleration of 1.41 m/s^2. I know the answer is 28N, but I haven't yet figured it out. I did F=ma F=(7.5)(1.41)cos13= 10.30 what didn't I do? thanks

:D Got it! Thanks for the help I really appreciate it. I'm a really slow learner lol. How did t0 end up at the bottom?

I don't really know how to rearrange equations, but would this be right? thanks Vo =t0-1/2*g*t0^2/sinA

I don't understand. I don't know v0 so how do I solve the equation?

I think so. >.< My book gives me equations but they all ask for V sub y and Vo but I don't have either...

How do I find initial velocity if I'm only given time and the angle above the horizontal? The only other info given is that the object is caught at the same level it is kicked.

awsome, got it. 8.80kg. I don't know how i mess these up. What are the steps you use to convert x = vt +1/2at^2 to a= 2x/t^2? thanks for your help.

At the local grocery store, you push a 15.2 kg shopping cart. You stop for a moment to add a bag of dog food to your cart. With a force of 12.0 N, you accelerate the cart from rest through a distance of 2.24 m in 3.00 s. What was the mass of the dog food? F=ma m=f/a I rearranged...

Got it. Thanks. 1.08 kN. I acually got it the first time, only typed it in wrong. omg this class is going to kill me. I'm sure to have another question with in the next 3 minutes...

ugh I've got problems with Newton again. >.< On vacation, your 1500 kg car pulls a 540 kg trailer away from a stop light with an acceleration of 2.00 m/s^2. What force does the trailer exert on the car? F=ma so: Force of car is 1.08 kN and Force of trailer is 3.0 kN. I thought it would...

In a grocery store, you push a 13.5 kg shopping cart with a force of 12.5 N. If the cart starts at rest, how far does it move in 3.00 s? Here's what I did: m=13.5 kg f=12.5 N t=3s v(i)=0 F=ma a=f/m 12.5/13.5=0.93m/s^2=accel. V(final)=0+at= 0+(.93)(3)=2.79 Vf^2=Vi^2+2a(deltax)= solve...

Oh! lol I'm so slow. Thanks all, I get it now.

The question is to convert: 8.4 m/s^2 into km/h^2 I did: 8.4m/s(1000km/1m)(3600s/1h)= Wrong. lol So what didn't I do right? I cancled out the m and s for km and h but according to my book this is wrong? Thanks