Which mode of transportation of heat is essentially not required for the medium?
Conduction
Convection
Radiation
All not required
The velocity of sound in air is taken as 332 m/s. If the pressure of a gas is taken double, then what will be the velocity of sound in air?
996 m/s
664 m/s
166 m/s
332 m/s
The escape velocity from the surface of the Earth is
11.2 km/s
11.2 m/s
11.2 cm/s
11.2 mm/s
A.
11.2 km/s
The escape velocity of the earth is the minimum speed needed for an object to escape from the gravitation attraction of the earth, without the aid of thrust or suffering the resistance from friction. This is given by
The composition percentage of CaO and SiO2 in Portland cement is
40-45% and 10-15%
85-90% and 40-45%
60-68% and 17-24%
3-10% and 80-90%
Examples of Web Browser are
(i), (v) and (vi)
(ii), (iii) and (iv)
(i), (ii) and (iii)
All of these
Asteroids are found in between the orbits of
Saturn and Jupiter
Mars and Jupiter
Earth and Mars
Saturn and Uranus
SONAR is used for
measuring distance, direction, and velocity of objects in the water
measuring distance, direction, and velocity of objects in the air
measuring the distance and direction of objects in the water
measuring direction and velocity of objects in air
Which of the statements about the reaction given below are incorrect?
2 PbO(s) + C (s) → 2Pb (s) + CO2(g)
(i) and (ii)
(i) and (iii)
(i), (ii) and (iii)
All of these