Eriosoma lanigerum, Woolly aphid, is an important pest in which of the following?
Woolly aphid is black aphid that sucks sap from woody stems of apple, cotoneaster and pyracantha and covers itself in a white waxy secretion. Aphids are sap-sucking true bugs and are an important part of many food chains, supporting many predators.
Tungsten is used for the manufacture of the filament of an electric bulb, because –
Newton’s second law of motion primarily explains which of the following?
Which of the following materials behaves as a dielectric?
Which law states that the total current entering a junction is equal to the total current leaving the junction?
A circular coil of wire consisting of 120 turns, each of radius 12 cm carries a current of 0.30 A. What is the magnitude of the magnetic field B at the ...
Match the following machines with their working principles:
(i) Electric motor - (a) Heat energy into mechanical energy
(ii) Steam engin...
What is colour of light related to?
What is the work done by a centripetal force on an object moving in a circular path at constant speed?
The correct option, if speeds of gamma rays, X-rays and microwave are Vg, Vx an Vm respectively will be
For a cell terminal potential difference is 3.5 V when circuit is open and reduces to 2.5 V when cell is connected to a resistance of R = 10Ω then...
