Finding time and distance with NLM.

[Sace Ver]

Homework Statement

A puck of mass 30 g slides across rough ice, experiencing a frictional force of 0.20N. If it was moving at 10km/h when it hit the ice patch,
(a) how much time did it take to stop?
(b) how long was the ice patch?

Given:
m=30g (0.03kg)
F_f=0.20N
V=10km/h (2.7m/s)[/B]

Homework Equations

Fnet=ma
a=v/t
v=d/t[/B]

The Attempt at a Solution

Fnet = ma
a = Fnet/m
a = 0.20N / 0.03kg
a = 6.6m/s²[/B]

a = v/t
t = v/a
t = 2.7m/s / 6.6m/s²
t = 0.40s

v = d/t
d = vt
d = (2.7m/s)(0.40s)
d = 1.08m

So therefore, it took 0.40s for the puck to stop. The ice patch was 1.08m.

 

[Sace Ver]

Homework Statement

A puck of mass 30 g slides across rough ice, experiencing a frictional force of 0.20N. If it was moving at 10km/h when it hit the ice patch,
(a) how much time did it take to stop?
(b) how long was the ice patch?

Given:
m=30g (0.03kg)
F_f=0.20N
V=10km/h (2.7m/s)[/B]

Homework Equations

Fnet=ma
a=v/t
v=d/t[/B]

The Attempt at a Solution

Fnet = ma
a = Fnet/m
a = 0.20N / 0.03kg
a = 6.6m/s²[/B]

a = v/t
t = v/a
t = 2.7m/s / 6.6m/s²
t = 0.40s

v = d/t
d = vt
d = (2.7m/s)(0.40s)
d = 1.08m

So therefore, it took 0.40s for the puck to stop. The ice patch was 1.08m.

Can someone check it over PLS and thank you!

 

[SammyS]

Homework Statement

A puck of mass 30 g slides across rough ice, experiencing a frictional force of 0.20N. If it was moving at 10km/h when it hit the ice patch,
(a) how much time did it take to stop?
(b) how long was the ice patch?

Given:
m=30g (0.03kg)
F_f=0.20N
V=10km/h (2.7m/s)[/B]

Homework Equations

Fnet=ma
a=v/t
v=d/t[/B]

The Attempt at a Solution

Fnet = ma
a = Fnet/m
a = 0.20N / 0.03kg
a = 6.6m/s²[/B]

a = v/t
t = v/a
t = 2.7m/s / 6.6m/s²
t = 0.40s

v = d/t
d = vt
d = (2.7m/s)(0.40s)
d = 1.08m

So therefore, it took 0.40s for the puck to stop. The ice patch was 1.08m.

The time is correct. The distance is not correct.

The velocity is not constant, so the average velocity is not 2.7 m/s.

 

[Sace Ver]

The time is correct. The distance is not correct.

The velocity is not constant, so the average velocity is not 2.7 m/s.

So would 2.7m/s be the initial velocity and then 0 would be my final velocity?

 

[SammyS]

So would 2.7m/s be the initial velocity and then 0 would be my final velocity?

The puck comes to a stop, so yes.

 

[Sace Ver]

The puck comes to a stop, so yes.

so it'd be d = 2.16?

 

[SammyS]

so it'd be d = 2.16?

Yes.

 

[Sace Ver]

Yes.

THANK U!