Yahoo Answers: Answers and Comments for Help please? Physics? [Physics]
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From Anonymous
enUS
Thu, 20 Jun 2019 03:05:04 +0000
3
Yahoo Answers: Answers and Comments for Help please? Physics? [Physics]
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https://answers.yahoo.com/question/index?qid=20190620030504AA9ycD9
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From electron1: A normal force is perpendicular to floor. Thes...
https://answers.yahoo.com/question/index?qid=20190620030504AA9ycD9
https://answers.yahoo.com/question/index?qid=20190620030504AA9ycD9
Thu, 20 Jun 2019 20:04:10 +0000
A normal force is perpendicular to floor. These two forces are the weight of weight of the bricks and the vertical component of the force. Since the direction of this force is upward, it will be negative force.
Weight = 17 * 9.8 = 166.6 N
Vertical = 166 * sin 23.7
Ne force = 166 – 166 * sin 23.7
This is approximately 99.3 N

From RealPro: I got 88.66 which seems wrong to me...
Noooo...
https://answers.yahoo.com/question/index?qid=20190620030504AA9ycD9
https://answers.yahoo.com/question/index?qid=20190620030504AA9ycD9
Thu, 20 Jun 2019 08:49:47 +0000
I got 88.66 which seems wrong to me...
Nooooo.....
Obviously your calculator mode is radians, please switch to degrees.
For this situation when speed is constant (no net force)
(T = tension in rope, n = normal force)
We analyze the vertical and horizontal sum of forces
Tcosθ  µn = 0
n  mg + Tsinθ = 0
n = mg / (1 + µ tanθ) = 202 N
Wf = Friction * displacement
= µn * 11.5 m
= 0.930 kJ to 3 s.f.
Since no net force is present and total work done is 0, then work done by the rope is +0.930 kJ.
You can also solve for Tcosθ and multiply by 11.5 m.
Had there been no friction, cart would gain 0.930 kJ of kinetic energy.