Transportation in Animals and Plants — Science STD 7 — Question

Why do you think lunar eclipses can be seen from a large part of the Earth when they happen, but total solar eclipse can be seen by only a small part of the Earth?

Explain the reason for the shiny reflectors of room heaters.

Explain with the help of a diagram, how does the magnetic effect of electric current help in the working of an electric bell.

Place a piece of bread in a moist and warm place for few days. Observe it after few days. What will you see?
(i) Name the organism that grows on the bread piece?
(ii) What are the thread-like projections called?
(iii) What is the knob-like structure present on the top of thin stem called?
(iv) Which type of reproduction does this organism show?

How is turmeric used as an indicator?

What health problems do workers in the silk industry suffer from?

Differentiate between nutrients and nutrition.

Briefly explain the maximum and minimum thermometers.

Name three natural indicators and how they work.

A train travels 180 km in 3 h. Find its speed in:
(i) km/h
(ii) m/s
(iii) What distance will it travel in 4h if it maintains the same speed throughout the journey?