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 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.

Answer 1

The temperature is 0.1714°C.

Step-by-step explanation:

Given that,

Distance = 7.50 cm

Frictional force = 40.0 N

Mass of tissues = 0.100 kg

Number of rubs = 20

We need to calculate the heat

Using formula of heat

`U=W=F* d`

`U=40.0*7.50*10^(-2)*20`

`U=60\ J`

We need to calculate the temperature

Using formula of heat

`Q= mc\Delta T`

`\Delta T=(Q)/(mc)`

Put the value into the formula

`\Delta T=(60)/(0.100*3500)`

`\Delta T=0.1714^(\circ)C`

Hence, The temperature is 0.1714°C.