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**1. Homework Statement**

Hi, I just want to know if I am on the right track with the answers I have came up. Thanks for everyone's help.

1. (a) Cathy takes the bus home form work. In her hand she holds a 2.0 kg cake box, tied together with a string. As she ascends the steps into the bus, the box accelerates upward at a rate of 2.5 m/s^2. What is the force exerted on the string?

(b) Cathy sets the box on the seat beside her. The bus accelerates form rest to 60.0 km/h in 4.0 s, and the box begins to slide. What is the coefficient of static friction between the box and the seat of the bus?

(c) A taxi suddenly cuts in front of the bus, causing the bus driver to slam on the brakes. The bus driver reduces speed from 60.0 km/h to 20.0 km/h in 1.5 s. Does Cathy's cake slide forward?

**2. Homework Equations**

F=m(a)

formula for finding the coefficient of friction (I think....)

U = F(k) / F(n)

**3. The Attempt at a Solution**

(a) F= m(a)

=(2.0 kg) (2.5 m/s)

=5 N

(b) U = F(k) /F(n)

=16.67 m/s /5 N

= 3.3

(c) My first inclination would be that Cathy's cake would slide. However, in tring to figure out how to prove this I wasn't quite sure except posssibly using the distance formula.

d=1/2 (v1 + v2) t

=1/2(60 m/s + 20 m/s) 1.5

=60 m

(this seems like an awful big number and doesn't make sense)

Am I missing a certain concept here?

Thanks for the help

Pharm89

**1. Homework Statement**

**2. Homework Equations**

**3. The Attempt at a Solution**