# 10th science Refresher Course 1 Answer English Medium

EVALUATION

### I. Fill in the Blanks

1.  The degree of hotness or coldness of a substance is __________________

2.  The SI unit of mass is _____________________

3.  One mole of a substance contains ___________________ atoms or molecules.

4.  _______________ clock uses the periodic vibrations accruing within the atom.

5.  Luminous intensity is measured by ____________________

Answer : photometer  luminous intensity meter

6. Heat energy given to a substance will __________________________ its temperature.

7.  Metre is the unit of ________

### II. Choose the correct answer

1. The amount of electric charges fl wing through a conductor in one second is _______

(a) Electric Current

(b) Resistance

(c) Electric potential

2.  The SI unit of temperature is ______________

(b) Fahrenheit

(c) Kelvin

(a) Celsius

3.  The SI unit of luminous intensity is________________

(b) Candela

(a) mole

(c) Ampere

### III. Make True / False

1.  The SI unit of electric current is kilogram. (True/false)

2.  A physical balance is more sensitive than a beam balance. (True/false)

3. Electric current is measured by an instrument called ammeter. Is it true or false?

4.  Atomic clocks are used in GPS devices.  Is it true or false?

### IV. Match the following

Physical quantities                       SI units

1.   a) Length                           kelvin d)

b) Mass                                   metre a)

c) Time                                    kilogram b)

d) Temperature                         second c)

Instrument                    Measuring  things

2.   a) Screw gauge         Vegetables c)

b) Vernier caliper               Coins  a)

c) Beam balance               Gold ornaments d)

d) Digital balance              Cricket ball b)

### 1.  How will you calculate Indian standard time (IST)?

• The location of Mirzapur in uttarpradesh is taken as the reference longitude of the Indian Standard Time. It is located at 82.5 degree longitude.

### 2.  What are the scales of temperature?

• Celsius, Fahrenheit,Kelvin

### 3.  Name the three hands used to show time in an analog clock.

• Hours hand,Minutes hand,Seconds hand

• one rotation

• Can't find.