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Luyando wants to have a bit of fun with her wagon. She puts her 12 baby sister, Waluse, on the wagon and pulls it across the floor using a rope at an angle of 22° above the floor. Using the spring balance that mum uses to weigh things in the kitchen, Luyando realises that the tension in the rope is constant and has a value of about 40 . Use the work-energy theorem to find Waluse’s speed after being pulled 4.0 across the living room. The coefficient of friction is 0.2 and the weight of the wagon is 3kg

1 Answer

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Answer:

work energy equation


w.d(external)= \delta \: k.e+ \: \: \ \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: w.d(ressesive)

Step-by-step explanation:

first of all we have to find reaction force to find fr


fr = \mu \: mg \\ mg = reaction \: force(r) \\ f = ma \\ r + 40 \sin(22) - 150 = 0 \\ r = 150 - 40 \sin(22)

then let's find friction


fr = \mu \: r \\ 0.2 * (150 - 40 \sin(22) )

then let's apply work energy principle...its on the 2nd picture

v = 2.3ms^-1

Luyando wants to have a bit of fun with her wagon. She puts her 12 baby sister, Waluse-example-1
Luyando wants to have a bit of fun with her wagon. She puts her 12 baby sister, Waluse-example-2
User Paolo B
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