Physics Class 11&12 questions - Statistics & analytics of Telegram channel @physics91172

1 863

A body starts from rest and travels for t second with uniform acceleration of 2 m/s². If the displacement made by it is 16 m, the time of travel t is

Anonymous voting

1 863

Which one of the following is the unit of velocity?

Anonymous voting

1 863

A body starts from rest and travels with uniform acceleration on a straight line. If its velocity after making a displacement of 32 m is 8 m/s, its acceleration is

Anonymous voting

1 863

A 180 metre long train is moving due north at a speed of 25 m/s. A small bird is flying due south, a little above the train, with a speed of 5 m/s. The time taken by the bird to cross the train is

Anonymous voting

1 863

A boy starts from a point A, travels to a point B at a distance of 3 km from A and returns to A. If he takes two hours to do so, his speed is

Anonymous voting

1 863

The displacement in metres of a body varies with time t in second as y = t2 – t – 2 . The displacement is zero for a positive of t equal to

Anonymous voting

1 863

Motion in a straight line👇

1 863

Motion in a straight line👇

1 863

NEET 33 years questions⬆️⬆️🆙

1 863

Ncert books app best on play store in my opinion👇 http://play.google.com/store/apps/details?id=letest.ncertbooks

1 863

The error associated with the resolution of the measuring instrument is called

Anonymous voting

1 863

Accuracy : The accuracy of a measurement is a measure of how close the measured value is to the true value of the quantity. Precision : Precision tells us what resolution or limit the quantity is measured. For example, suppose the true value of a certain length is near 3.678 cm. In one experiment, using a measuring instrument of resolution 0.1 cm, the measured value is found to be 3.5 cm, while in another experiment using a measuring device of greater resolution say 0.01 cm the length is determined to be 3.38 cm the first measurement has more accuracy (because it is closer to the true value) but less precision (its resolution is only 0.1 cm), while the second measurement is less accurate but more precise. Thus every measurement is approximate due to errors in measurement. In general, the errors in measurement can be broadly classified as (1) systematic errors and (2) random errors.

1 863

You may notice that there is an interesting coincidence between the numbers appearing in ranges of lengths and time intervals. Note that the ratio of the longest and shortest lengths of objects in our universe is about 10⁴¹. Interestingly enough, the ratio of the longest and shortest time intervals associated with the events and objects in our universe is also about 10⁴¹. This number, 10⁴¹ comes up again in the ranges of masses which lists typical masses of objects. The ratio of the largest and smallest masses of the objects in our universe is about (10⁴¹)² Is this a curious coincidence between these large numbers purely accidental ? (Reference: NCERT)

1 863

Range and order of time intervals

1 863

We now use an atomic standard of time which is based on the periodic vibrations produced in a

Anonymous voting

1 863

Range and order of masses

1 863

Range and order of lengths

1 863

Mass of an object does not depend on

Anonymous voting

1 863

For what purpose the parallax method is used for ?

Anonymous voting

1 863

THE INTERNATIONAL SYSTEM OF UNITS In earlier time scientists of different countries were using different systems of units for measurement. Three such systems, the CGS, the FPS (or British) system and the MKS system were in use extensively till recently. The base units for length, mass and time in these systems were as follows : • In CGS system they were centimetre, gram and second respectively. • In FPS system they were foot, pound and second respectively. • In MKS system they were metre, kilogram and second respectively. The system of units which is at present internationally accepted for measurement is the Système Internationale d’ Unites (French for International System of Units), abbreviated as SI. The SI, with standard scheme of symbols, units and abbreviations, developed by the Bureau International des Poids et measures (The International Bureau of Weights and Measures, BIPM) in 1971 were recently revised by the General Conference on Weights and Measures in November 2018. The scheme is now for international usage in scientific, technical, industrial and commercial work. Because SI units used decimal system conversions within the system are quite simple and convenient. (Reference: NCERT)