This question pertains to a video clip from the movie Tangled. In the video she

Question

This question pertains to a video clip from the movie Tangled. In the video she jumps and her hair swings her to the ground, she then skids 6 meters. At the bottom of the swing assume Rapunzels hair is straight up and down when she lets go. She skids to a stop about 6 meters. the radius of her swing is about 10 meters and Rapunzel has a mass of 50kg.

Find the force exerted by her hair. To do this you will need to solve a sub problem and make a time measurement after she has let go of her hair. I meaured the time she was swinging that was a 11 seconds. the time she was skidding was 1 second.

According to an Internet source for single string can potentially carrie a wheight of up to 100 grams. A.) use your answer to #3, to determine the minimum number of hair strands that rapunzel must have to perform this swing B.) Do a quick web search to find the average number of strands of hair on a human head. C.) From your answers, is Rapunzel's hair of normal strength or above average strength.

After she has let go of her hair, she skids to a stop. A) Draw a force diagram while she is skidding and label the forces. B.) determine the coefficient of kinetic friction between rapunzel and the ground.

Explanation / Answer

While skiding, lets her initial velocity =u, and final velocity = 0, given t = 1 s

v = u +at

0= u +a

a=-u

also,

s = ut + 0.5 at2

6 = u - 0.5u = 0.5u

u = 12 m/s

T- mg = mu2/R

T = mg + mu2/R = 50*9.8 + 50*12*12/10 =490+720 = 1210 N

according to your internet search, force 1 hair can carry = 100 grams *9.8m/s2 = 0.98 N

number of hairs Rapunzel must have = 1210 /(0.1*9.8) = 1235

avg number of strands of hair in human head = 100000

s = u + 0.5 u

u2 / r =a

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.