WorksheetsUNITS & MEASUREMENTS
Total questions: 30
Worksheet time: 16mins
The number of significant figures in 0.06900 is
5
4
3
2
The sum of the numbers 436.32, 227.2 and 0.301 in appropriate significant figures is
663.821
664
663.8
663.82
The mass and volume of a body are 4.237 g and 2.5 cm3,respectively. The density of the material of the body in correct significant figures is
1.6048 g cm–3
1.69 g cm–3
1.7 g cm–3
1.695 g cm–3
The numbers 2.745 and 2.735 on rounding off to 3 significant figures will give
2.75 and 2.74
2.74 and 2.73
2.75 and 2.73
2.74 and2.74
The length and breadth of a rectangular sheet are 16.2 cm and10.1cm, respectively. The area of the sheet in appropriate significant figures and error is
164 ± 3 cm2
163.62 ± 2.6 cm2
163.6 ± 2.6 cm2
163.62 ± 3 cm2
Which of the following pairs of physical quantities does not have same dimensional formula?
Work and torque.
Angular momentum and Planck’s constant.
Tension and surface tension.
Impulse and linear momentum
Measure of two quantities along with the precision of respective measuring instrument is
A = 2.5 m s–1 ± 0.5 m s–1
B = 0.10 s ± 0.01 s
The value of A B will be
(0.25 ± 0.08) m
(0.25 ± 0.5) m
(0.25 ± 0.05) m
(0.25 ± 0.135) m
A physical quantity X is given by X=a2b3/cd1/2.If the percentage error in measurement of a,b,c,d are 4%,3%,2%,1% respectively .Then percentage error in X will be
10%
20%
19%
19.5%
Which of the following measurements is most precise?
5.00 mm
5.00 cm
5.00 m
5.00 km.
The mean length of an object is 5 cm. Which of the following measurements is most accurate?
4.9 cm
4.805 cm
5.25 cm
5.4 cm
Young’s modulus of steel is 1.9 × 1011 N/m2. When expressed in CGS units of dynes/cm2,
1.9 × 1010
1.9 × 1011
1.9 × 1012
1.9 × 1013
If momentum(P), area(A) and time (T) are taken to be fundamental quantities, then energy has the dimensional formula
(P1 A–1 T1)
(P2 A1 T1)
(P1 A–1/2 T1)
(P1 A1/2 T–1)
MORE THAN ONE ANSWER:- If P, Q, R are physical quantities, having different dimensions, which of the following combinations can never be a meaningful quantity :
(P – Q)/R
PQ – R
PQ/R
(PR – Q2)
(R + Q)/P
MORE THAN ONE ANSWER :- Which of the following ratios express pressure?
Force/ Area
Force/ Volume
Energy/ Area
Energy/ Volume
MORE THAN ONE ANSWER:- Which of the following are not a unit of time?
Second
Parsec
Year
Light year
The value of universal gravitational constant in SI system is G=6.67 x 10-11kg-1m3s-2. The its value in cgs system will be
6.67 x 10-11
6.67 x 10-8
6.67 x 10-6
6.67 x 10-5
Three measurements are, a b = = 25.6, 21.1 and c = 2.43. Find the
value a -b- c to correct significant figures is.......
2.07
2.1
2
2.0
A force F is applied on a square plate of side L. If the percentage error in the determination of L
is 2% and that in F is 4%. What is the permissible error in pressure?
8%
6%
4%
2%
The viscous force F on a sphere of radius a moving in a medium with velocity v is given by
F a v = 6π η . The dimensions of η are
ML−3
MLT−2
MT−1
ML − 1T−1
A force is given by
F =at+ bt2
where, t is the time. The dimensions of a and b are
MLT–4 and MLT
MLT–1 and MLT0
MLT–3 and MLT–4
MLT–3 and MLT0
Which of the following sets cannot enter into the list of fundamental quantities in any system of
units?
length, mass and density
length, time and velocity
mass, time and velocity
length, time and mass
If force F, length L and time T are taken as fundamental units, the dimensional formula for mass will be
FL T−1
FLT−2
FL-1 T-1
FL5T2
If unit of length and time is doubled, the numerical value of g (acceleration due to gravity) will be
doubled
halved
four times
same
Choose the wrong statement.
All quantities may be represented dimensionally in terms of the base quantities
A base quantity cannot be represented dimensionally in terms of the rest of the base
quantities
The dimension of a base quantity in other base quantities is always zero
The dimension of a derived quantity is never zero in any base quantity
If the energy ( ), E velocity ( ) v and force ( ) F be taken as fundamental quantities, then the
dimensions of mass will be
Fv−2
Fv−1
Ev−2
Ev2
Given equations
α/ t2 = Fv+ β/x2 (here t = time, F = force, v = velocity, x = distance) . Then dimension formula for [α ] and [ β] will be respectively .
ML3 T-4 & ML2T-1
ML4 T-3 & ML2T-1
ML2T-1 & ML4 T-3
ML4 T-3 & ML2T-1
The length and breadth of a metal sheet are 3.124 m and 3.002 m respectively. The area of this
sheet upto correct significant figure is
9.378 m2
9.37 m2
9.4 m2
None of these
Let g be the acceleration due to gravity at the earth’s surface and K the rotational kinetic
energy of the earth. Suppose the earth’s radius decreases by 2%. Keeping all other quantities
constant, then
g increases by 2% and K increases by 2%
g increases by 4% and K increases by 4%
g decreases by 4% and K decreases by 2%
g decreases by 2% and K decreases by 4%
If error in measurement of radius of a sphere is 1%, what will be the error in measurement of volume?
1%
1/3%
3%
None of these
The resistance R = V/I
where V = (100 ±5.0 ) V and I = ( 10± 0.2 ) A. Find the percentage error in R.
5.2%
2.5%
0.7%
7%
