Measuring Length

Q.

Name the three convenient units used to measure length ranging from very short to very long value. How are they related to the S.I. unit ?

Q. The SI unit of distance is ___ .

Q.

What is parsec?

Q.

A boy measures the length of a pencil and expresses it to be 2.6 cm. What is the accuracy of his measurement ? Can he write it as 2.60 cm ?

Q.

What is measurement? How is a measurement expressed?

Q.

Name two units of length which are bigger than a metre. How are they related to the metre ?

Q. The size of a human hair strand is about 0.12 mm. Express it in the unit of angstrom.

1. 1200000

Q.

Convert 1 light year into km

1. $9.46\times {10}^{15}m$

2. $9.46\times {10}^{12}m$

3. $9.46\times {10}^{12}km$

4. $9.46\times {10}^{15}km$

Q.

Write the names of two units of length smaller than a metre. Express their relationship with metre.

Q. Convert $1$ $g/c{m}^3$ to $kg/m^3$

1. 1000
2. 100
3. 0.1
4. 10

Q. What is spectroscopy

Q.

The side of a cube is measured by a vernier calliper (10 divisions of a vernier scale coincide with 9 divisions of the main scale, where 1 division of the main scale is 1 mm). The main scale reads 10 mm and the first division of vernier scale coincides with the main scale. Mass of the cube is 2.736 g. Find the density of the cube inappropriate significant figures.

1. None of these

2. 

3. 

4. 

Q.

Angstrom is a unit of___ .

Q.

Assertion (A): The accuracy of a standard screw gauge is more than the accuracy of a standard vernier caliper.

Reason (R): The least count of standard screw gauge is more than the least count of standard vernier caliper.

1. A and R are true and R is the correct explanation of A.

2. A and R are true, but R is not the correct explanation of A.

3. A is true but R is false.

4. Both A and R are false.

Q. One kilometre is thousand times the length of one metre.

1. True
2. False

Q.

How is nanometre related to Angstrom ?

Q.

How many nanometers are there in $1cm$ $?$

Q.

Which unit of measurement will you use to find the area of your drawing room.

Q.

Complete the following :

(a) 1 light year = .......................... m

(b) 1 m = ............................. $A^{\circ }$

(c) 1 m = ...............................µ

(d) 1 micron = ................................$A^{\circ }$

(e) 1 fermi =.................................. m

Q.

State SI and practical units of electrical energy.

Q.

The least count of a metre rule is?

1. 1m

2. 0.01cm

3. 0.1cm

4. 1cm

Q.

A kilowatt-hour is a unit of ________?

Q.

A Vernier caliper has 1 mm marks on the main scale. It has 20 equal divisions on the Vernier scale which matches with 16 main scale divisions. For this Vernier caliper, the least count is:

1. 0.02 mm

2. 0.05 mm

3. 0.1 mm

4. 0.2 mm

Q.

Which of the following is not a unit of length?

1. micron

2. light year

3. angstrom

4. radian

Q. The thickness of the wall of a chemical laboratory test tube is $0.2566cm$. Which of the following could have been the measuring instrument used to find the thickness value?

1. Ordinary screw gauge
2. Micrometre screw gauge
3. Ordinary vernier callipers
4. Metre ruler

Q. A vernier calipers have $1mm$ marks on the main scale. It has $20$ equal divisions on the vernier scale which matches with $16$ main scale divisions. For this vernier calipers, the least count is :

1. $0.02mm$
2. $0.05mm$
3. $0.1mm$
4. $0.2mm$

Q.

Does the weight scale actually measure the weight or the mass ?

Q.

A frog jumps $2$m $28$cm and the other frog jumps $48$cm less than the first frog. What distance did the second frog jump?

Q.

Why gold is not weighed by a spring balance

Q.

RELATE ONE ANGSTROM TO NANOMETRE