Question

Rubbing your hands together warms them by converting work into
thermal energy. If a woman rubs her hands back and forth for a
total of 10 rubs a distance of 7.50 cm each and with a frictional
force averaging 50.0 N, what is the temperature increase? The mass
of tissue warmed is only 0.100 kg, mostly in the palms and
fingers.

_________

Answer #1

Work = Ff * Total distance in meters

7.50 cm = 0.075 m, Distance back and forth = 0.150 m

Total distance = 10 * 0.150 = 1.5 m

Work = 50 * 1.5 = 75 N * m

This is the amount of thermal energy which was transferred to the
tissue.

?Q = mass * Specific heat * ?T

You need to know the specific heat of the tissue.

According to the website below, the average specific heat of the
human body is 3470 J/(kg * ?C)

http://www.engineeringtoolbox.com/human-body-specific-heat-d_393.html

75 = 0.1 * 3470 * ?T

?T = 75

1. Rubbing your hands together warms them by converting work
into thermal energy. If a woman rubs her hands back and forth for a
total of 16 rubs, at a distance of 7.50 cm per rub, and with a
frictional force of 40.0 N, what is the temperature increase in
degrees Celsius? The mass of tissue warmed is only 0.100 kg, mostly
in the palms and fingers. ____ °C.

rubbing your hands together warms them by completing
work into thermal energy. If a woman rubs her hands back-and-forth
for a total of 20 rubs, at a distance of 7.50 cm per rub, and with
an average frictional force of 40.0N, what is the temperature
increase? The mass of tissues warmed up is only 0.100 kg, mostly in
the palms and fingers.

Rubbing your hands together warms them by converting work into
thermal energy. If a woman rubs her hands back and forth for a
total of 20 rubs, at a distance of 7.50 cm per rub, and with an
average frictional force of 40.0 N, what is the temperature
increase? The mass of tissues warmed is only 0.100 kg, mostly in
the palms and fingers.
They use the formula Q=NFd
I do not understand this formula or its derivation. It is...

If a woman rubs her hands back and forth for a total of 20 rubs,
at a distance of 5.3 cm per rub, and with an average frictional
force of 32.3 N, what is the temperature increase? The mass of
tissues warmed is only 0.104 kg, mostly in the palms and fingers.
Use a specific heat of 3500 J/kgºC.

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 25 minutes ago

asked 59 minutes ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 3 hours ago