2. HAMMER THROW: When a stone is tied at one end of a string and is rotated from the other end then the stone will describe a circle. If we suddenly stop the motion, the stone will go in a directior
tangential to the circular motion.
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(i) The number of tangent/s can be drawn at point 'm' in the above figure is
(a) 1
(b) 2
(c) O
(ii) If mV ll TM, then 2rMm = ?
(d) infinite
(a) 60°
(b) 90°
(c) 30°
(d) 1800
(iii) Given that mM = 8 cm, MV = 10 cm, find mV?
(a) 6 cm (b) 12 cm (c) 15 cm
(iv) When an athlete leaves the string after many revolutions of stone over his/her head,
(d) 4 cm
moves in
path.
(a) straight (b) circular (c) tangential (d) elliptical

Each of the following data sets has a mean of x = 10. (i) 8 9 10 11 12 (ii) 7 9 10 11 13 (iii) 7 8 10 12 13 (a) without doing any computations, order the data sets according to increasing value of standard deviations. (i), (iii), (ii) (ii), (i), (iii) (iii), (i), (ii) (iii), (ii), (i) (i), (ii), (iii) (ii), (iii), (i) (b) why do you expect the difference in standard deviations between data sets (i) and (ii) to be greater than the difference in standard deviations between data sets (ii) and (iii)? hint: consider how much the data in the respective sets differ from the mean. the data change between data sets (i) and (ii) increased the squared difference îł(x - x)2 by more than data sets (ii) and (iii). the data change between data sets (ii) and (iii) increased the squared difference îł(x - x)2 by more than data sets (i) and (ii). the data change between data sets (i) and (ii) decreased the squared difference îł(x - x)2 by more than data sets (ii) and (iii). none of the above