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Matter In Our Surroundings - Matter can be defined as anything that occupies space, (i.e., has a volume), possesses mass, offers resistance and can be felt through one or more of our sense..

Question: An object undergoes an acceleration of 8 m/s 2 starting from rest. Find the distance travelled in one second. Answer: Time (t) = 1 s Distance travelled (S) = ? Initial velocity (u) = 0 [object is starting from rest] Distance covered = 4 m..

Question: Figure shows a snap shot of a wave form of frequency 50 Hz in a string. The number in the string represent distance in centimeter. For this wave motion, find: (a) wavelength (b) amplitude, and (c) velocity Answer: (a) 20 cm (b) 4 cm (c) v = f =..

Question: A bullet of mass 10 g passing through a 10 cm plank, has its velocity reduced from 300 m/s to 200 m/s. Find the average resistance offered to the bullet. Answer: Distance moved by the bullet = Thickness of the plank = S Initial velocity = 300 ..

Question: A force of 4 x 10 - 3 N acts on a mass of 0.04 kg over a distance of 20 m. Assuming the mass is initially at rest, find the final velocity. Answer: Mass (m) = 0.04 kg Distance (S) = 20 m Initial velocity (u) = 0 Use III equation of motion t..

Question: A truck of mass 5000 kg starts from rest and rolls down a hill with constant acceleration. It travels a distance of 800 metres in 20 seconds. Find its acceleration. Answer: F = ma Mass (m) = 5000 kg Initial velocity (u) = 0 [ starting from rest] F..

Question: A certain non-metal X forms two oxides I and II. The mass percentage of oxygen in oxide I (X 4 O 6 ) is 43.7, which is same as that of X in oxide II. Find the formula of the second oxide. Answer: Now 43.7 parts of oxygen in I corresponds to = 6 ..

Question: A car of mass 800 kg, moving at 108 km/h is brought to rest over a distance of 15 m. Find the retarding force developed by the brakes of the car. Answer: Initial velocity (u) = 108 km/hr = 30 m/s Final velocity (v) = 0 Distance covered (S) = 15 ..

Question: Give the range of frequencies of infrasonic, audible and ultrasonic and mention one use of each of them. Answer: Infrasonic frequency is below 20 Hz Use: to drill holes in rocks. Audible sound frequency range 20 Hz to 20,000 Hz. Use: means of communicat..

Take about 25 ml of a vegetable oil such as castor oil or groundnut oil in a beaker. Add about equal volume of concentrated solution of caustic soda (sodium hydroxide) to it. Heat the mixture slowly with stirring until it boils and a creamy paste of soap is formed. Boil further for 10-15 minutes. A..