In an experiment to measure the density of iron, the following data was obtained. book value is 7.86 g/cm3. one of the two sets of data is more precise, while one is more accurate. which of these two sets has the greater precision and which has the greater accuracy
(a) 7.72, 7.74. 7.73. 7.75, 7.74
(b) 7.86, 7.90, 7.78, 7.93, 7.83
which is more precise?
which is more accurate?

(a) is more precise

(b) is more accurate

Explanation:

When a given set of values are precise, this implies that all the values are close to each other but may not be accurate. But a set of values are accurate when they are compared and it can be observed that they are close to a given measured value. So we can infer that the values in option (a) are precise, while that in (b) are accurate when compared with the book value given.

here we know that ball will drop down by total distance 3.2 m

so here we know that

now using kinematics

now in the same time it will cover horizontal distance of 0.75 m

so speed of the ball will be

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.