A. Aluminium B. Selenium C. Barium D. None of these The photoreceptor drum in the heart of the system is basically a metal roller covered by a layer of photoconductive material. This layer is made out of a semiconductor such as selenium, germanium or silicon.
A. Western lights B. Southern lights C. Eastern lights D. Northern lights The aurora borealis, also known as the ‘northern lights’, is one of the most spectacular displays in the night sky. An aurora, also known as the polar lights or aurora polaris, is a natural light display in Earth’s sky, predominantly seen in high-latitude … Read more
A. A Infrared waves B. Radio waves C. Microwaves D. All of these Wireless transmission can be done via any of the infrared waves ,Radio waves or microwaves.
A. More than 100 B. More Than 200 C. More than 300 D. More than 400 According to NASA’s website, there are 214 moons in the solar system: 158 confirmed moons and 56 provisional moons—ones we suspect may be there or have spotted once but haven’t yet confirmed.
A. Ovum B. RBCs C. Sperm cell D. Neuron The largest cell is the ovum in the human body. The ovum also called the egg cell is the reproductive cell in the female body. Ovum is 20 times bigger than the sperm cells and has a diameter of about 0.1 mm.
A. ‘Higgs boson particles’ were detected. B. Gravitational waves’ were detected. C. Possibility of inter-galactic space travel through ‘wormhole’ was confirmed. D. It enabled the scientists to understand ‘singularity’. ‘Gravitational waves’ were detected. Billions of light-years away from the earth, two black holes have collided to create a larger one. Gravitational waves are created when … Read more
A. Radio waves B. Lasers C. Infrared waves D. Ultrasonic waves
A. Cerebrum B. Cerebellum C. Thalamus D. Medulla oblongata The cerebellum is located behind the brain stem. While the frontal lobe controls movement, the cerebellum “fine-tunes” this movement. This area of the brain is responsible for fine motor movement, balance, and the brain’s ability to determine limb position.
A. Digestion B. Respiration C. Reproduction D. Excretion Reproduction is a biological process in which an organism produces young ones (offspring ) of the same species. It is one of the most important characteristics of the living organisms. Reproduction is essential for the survival of species but not for the survival of individuals.
A. Hindbrain B. Hypothalamus C. Hippocampus D. Midbrain The pituitary gland is no larger than a pea, and is located at the base of the brain. The gland is attached to the hypothalamus (a part of the brain that affects the pituitary gland) by nerve fibers and blood vessels.