Aspecial standard weight, known to weight 10 n to high accuracy, is used to check the accuracy of two spring scales. on the first scale the weight gives a reading of 8.4 n. on the second scale the weight gives a reading of 9.1 n. the percent difference between the measurements of the two scales is %. (never negative.)

16 % and 9 %

Explanation:

Accurate reading = 10 N

reading of first balance = 8.4 N

reading of second balance = 9.1 N

Percentage difference in first reading

=

= = 16 %

Percentage difference in second reading

=

= = 9 %

second mirror gathers light from a faraway object and reflects it to another mirror. - a.

initial speed when it is dropped is 150 ft/s

now at the same moment the acceleration due to gravity is perpendicular to its velocity

so as we know that

now we have centripetal acceleration a = 32 ft/s^2 as its perpendicular to velocity

while tangential acceleration at the same moment will be zero

so

now radius of curvature is given as

so the radius of curvature just after it is dropped is 703.125 ft