Which of the following material/s is/are NOT used in making detergent?
a) washing soda
b) baking soda
c) borax and oil (optional)
d) glycerine
Designing A Concave Mirror Type Solar Cooker:
Solar radiation can be considered as one of the most suitable energy source to be used for cooking food. It is therefore important to promote advancement in solar cooking systems, in particular as concerns their efficiency and cooking times. In this work, we designed, realized and tested a novel low-cost solar cooker that uses a high-performance light-concentrating Fresnel lens, which is able to concentrate onto a small focal area a large amount of solar radiation. The radiation is then reflected by a mirror towards a cooking surface, where a pot can be located. The cooker has a geometrical concentration ratio of 40.97.
What happens to object when placed directly in sunlight?
a) it gets warm and hot
b) it gets cooled
c) it gets charged
d) it becomes conductor
Which mirrors have the inside surface of the spherical section is made reflecting?
a) plane
b) concave
c) convex
When a beam of
light is directed toward a concave mirror along principal axis, it converges
on………
a) pole
b) focus point
c) behind the focus point
d) in front of focus point
Which of the following mirror/s is/are used to focus the sunlight to a single point?
a) plane
b) concave
c) convex
