Q1. The frequency of direct current is ____________
(b) 50 HZ
(c) 60 HZ
(d) 100 HZ
Q2. The term ‘Higgs Boson’ is associated with –
(a) Nano Technology
(c) God Particle
(d) Stem Cell Research
Q3. Which term is not associated with sound wave?
Q4. What is the fundamental unit of amount of a substance?
Q5. Which one of the following is a good electrical conductor?
Q6.Which of the following pairing is incorrect?
(a) Hygrometer – Water vapour content of the atmosphere
(b) Lactometer – Specific gravity of liquids
(c) Anemometer – Speed of the wind
(d) Seismograph – Earthquakes
Q7. Diamond does not conduct electricity, because –
(a) It’s structure is very compact
(b) It is of crystalline nature
(c)There are only carbon atoms present in it
(d) No free electrons are present in it
Q8. Why is weightlessness experienced while orbiting the earth in space ships?
(c) Zero gravity
(d) Orbital motion
Q9. Sextant is an instrument used in which of the following?
(a) Cloud cover
(d) Medical treatment
Q10. Arithmometer was invented by –
(a) Evangelista Torricelli
(b) Charles Xavier Thomas
(c) Edward Teller
(d) Charles Babbage
Sol. DC implies no changes in value. Frequencies of signals are defined by how many changes per time, e.g. 60 cycles per second. In case of DC with there are 0 changes per second. Hence the frequency of DC is zero.
Sol. The term ‘Higgs Boson’ is associated with God particle.
Sol. Candela is not related to sound. It is unit of light intensity.
Sol. The mole is the unit of measurement for amount of substance in the International System of Units (SI). The unit is defined as the amount or sample of a chemical substance that contains as many constitutive particles.
Sol. Graphite is a very good conductor of electricity due to the mobility of the electrons in its outer valence shells.
Sol.A lactometer is an instrument used to check purity of milk.
Sol.Diamond is a bad conductor of electricity but good conductor of heat. Electricity is conducted in a crystal by electrons that are relatively free. But in diamond, each carbon atom is covalently bonded with four other carbon atoms and there are no free electrons.
Sol. Weightlessness experienced while orbiting the earth in space ships is due to Zero gravity.
Sol.The sextant is an instrument used to measure angles. Mainly used at sea, the tool is so named because its arc is one sixth of a circle – 60 degrees.
Sol.The Arithmometer was the first digital mechanical calculator strong enough and reliable enough to be used daily in an office environment. It was invented by Charles Xavier Thomas.