A solar shower

A solar shower

Pencil and paperOnline interactive
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Further Resources
This task is about explaining how a solar shower works.
Solar showers have bags which can hold up to 50 litres (L) of water.
If the bag is left on the ground in the Sun for a number of hours, the temperature of the water in it may rise to over 40 °C.
diagram of solar shower in the sun

Question 2Change answer

a)  Give a detailed description of why the water heats up.

Question 2Change answer

b)  Explain why the top surface of the bag is made of clear plastic.

Question 2Change answer

c)  Explain why the inside bottom surface of the bag is black.

Question 2Change answer

d)  Explain why the outside bottom surface of the bag is silver.

Question 2Change answer

e)  What temperature change would you expect if the solar shower bag was left in the Sun with the silver side facing upwards?
Task administration: 
This task can be completed with pencil and paper or online (with NO automarking).
Level:
5
Curriculum info: 
Science, Knowledge, Physical World
Keywords: 
using physics, energy, heat, radiation, solar shower
Description of task: 
Students are provided with a diagram of a bag used in solar showers. They answer questions about this bag relating to heat absorption, heat transfer, and radiation.
Answers/responses: 
  Y11 (04/2001)
a) Water (molecules) absorbs energy from the Sun. difficult
b) So energy from the Sun can pass into the bag. moderate
c)
 
 Absorbs heat.
Radiates heat back into the water.		 very difficult
very difficult
d) Prevents heat loss from the bag/to insulate the bag. difficult
e) Little/no temperature change. easy