NEB preperation-Just learn

10/06/2020

1. Big bang theory was proposed by
(a) Einstein
(b) Nicholus
(c) Gamnow & Le maitre
(d) Gali Leo
2. In big bang theory, the term big bang means
(a) Explosion (b) Condensation
(c) Fusion (d) Scattering
3. Which theory is most satisfactory theory about the origin of universe?
(a) Big bang theory (b) Pulsating theory
(c) Steady state theory (d) All of above
4. Which theory tells tat galaxies are moving away and away from each other & universe is expanding?
(a) Pulpating theory (b) Bigbang theory
(c) Steady state theory (d) None of above
5. Number of stars in our universe is
(a) 10^25 (b) 10^24
(c) 10^23 (d) 10^22

04/06/2020

Some instruments used in practice
1. Thermometer: Instrument used to measure temperature.
2. Altimeter: Instrument used to measure height.
3. Fathometer: Instrument used to measure depth.
4. Speedometer: Instrument used to measure speed.
5. Barometer: Instrument used to measure atmospheric pressure.
6. Manometer: Instrument used to measure pressure in the lungs and roots.
7. Sphygmomanometer: Instrument used to measure blood pressure.
8. Calorimeter: Instrument used to measure amount of heat.
9. Hygrometer: Instrument used to measure the relative humidity
10. Hydrometer: Instrument used to measure the relative density or specific gravity.
11. Ammeter: Instrument used to measure the strength of an electric current.

04/06/2020

Types of force
a. Gravitational force: It is the force between any two objects in the universe. It is long range but weak force and always attractive in nature.
b. Electrostatic force (Coulomb force)
• It is the force between change particles.
• It is the strongest force.
• It may be either attraction or repulsive.
c. Frictional force:
• It is a force which always opposes the relative motion between two solid surface.
• Work done by frictional force is always negative.
d. Magnetic force: It is the force due to magnets.
e. Viscous force: It is the force which always oppose relative motion between the layers of the fluid (liquid or gas).
f. Centripetal force: It is the inward force necessary for a body to keep moving in a circular path.
g. Centrifugal force: It is the outward force experienced by a body moving in a circular path.
h. Adhesive force: It is the force acting between dissimilar types of molecules. eg. Force acting between glass and water.
i. Cohesive force: It is the force acting between same type of molecules is cohesive force.
• It is attractive force.
eg. Force between mercury molecules.
j. Nuclear force: It is the force acting in between particles of the nucleus is called nuclear force (i.e. force between proton-proton, neutron proton, neutron-neutron)
• It is short ranged strong force.

18/05/2020

# Trignometry

02/05/2020