Physics - Spectrum Questions

Q .1. Give one useful and one harmful effect of ultra violet radiation on the human
body. 

Q .2. Explain briefly how white light gets dispersed by a prism. 

Q .3. Name the extreme colours in a pure spectrum of light. 

Q .4. Name any four regions of electromagnetic spectrum (other than visible light)
in increasing order of wavelength.

Q .5. Name any two electromagnetic waves which have a frequency higher than that
of violet light. State one use of each.

Q .6. Why are infrared radiations preferred over ordinary visible light for taking
photograph in fog ?

Q .7. A TV station transmits waves of frequency 200 MHz. Calculate the wavelength of the waves if  their speed in air is 3.0 × 10⁸ m s^-1.

Q .8. a)State the equation for the relation between frequency and wavelength of light in vacuum.

b) How does the speed of light in glass change on increasing the wavelength of
light ?

Physics numericals class 10 ICSE

1.      A body of mass 5 kg is taken from a height 5m to 10m. Find the increase in its potential energy(g=10m/sec2)

2.      How fast should a man of mass 60 kg run so that his kinetic energy is 750 J?

3.      A truck weighing 5 * 10³ kgf and a cart weighing 500 kgf are moving with the same speed. Compare their Kinetic energies?

4.      A ball of mass 10 g falls from a height of 5m. It rebounds from the ground to 4m. Find

a.      The initial potential energy of the ball

b.      The K.E of the ball just before striking the ground

c.       The K.E of the ball after striking the ground

d.      The loss in K.E on striking the ball

5.      A spring is compressed in a toy cart of mass 150 g. On releasing the cart, it moves with a speed of 0.2 m/sec. Calculate the potential energy of the spring

6.      A two gear system has one wheel with 50 teeth and the other wheel with 5 teeth. Find the gain in speed and gain in torque which can be obtained by their combinations. What is gear ration in each case?

7.      A gear system has the driving wheel of radius 18 cm and 100 teeth. It rotates at a speed of 30 rpm. If the speed of the rotation of the driven wheel is 150 rpm, find : i) the gear ratio    ii) the no of teeth of the driven wheel   iii) the radius of the driven wheel.

8.      Draw a diagram showing the combination of a movable pulley P1 with a fixed pulley P2 used for lifting up a load W.   a)  State the function of the fixed pulley P2.         b) If the free end of the string moves through a distance x, by what distance is the load W raised ?   c) What effort has to be applied to C to just raise the load W= 20 kgf?

9.      A block and tackle system has two pulley in each block, with the tackle tied to the hook of the lower block and the effort being applied upwards.         a) Draw a neat diagram to show this arrangement and calculate its mechanical advantage     b) If the load moves x distance, by what distance will the free end of the string moves

10.  A pulley system with a velocity ratio of 4 is used to lift a load of 150 kgf through a vertical height of 20 m. The effort required is 50kgf in the downward direction. Calculate:        a) the distance moved by the effort  b) the work done by the effort        c) the mechanical advantage           d) the efficiency of the pulley system e) the total number of pulleys and the number of pulleys in each block (take g=10)

Heat

1.      An iron ball requires 5000 j heat energy to raise its temperature by 10 degree celcius. Calculate the heat capacity of the iron ball

2.      A body of mass 500g requires 3000 J of heat energy in order to raise its temperature from 35^oC to 45 ^oC . Calculate the specific heat capacity of the body.  

3.      40 g of water at 60 ^oC  is poured into a vessel containing 50 kg of water at 20 ^oC. The final temperature of the mixture is 30 ^oC . Taking the specific heat of water as 4.2Jg^-1K^-1. Calculate the thermal capacity of the vessel.

4.      How much heat energy is required to melt 5 kg of ice? Specific heat of ice is 336 Jg^-1

work power and energy class 10

Question-1
(a) Define work and write its S.I unit.          [2 Mark]
(b) Define energy and establish relationship between S.I unit & commercial unit of energy.         [2 Mark]
(c)Two bodies A and B of masses 1 kg and 4 kg respectively have equal momentum find ratio of their K.E.        [2 Mark]

Question-2
(a) The work done by the heart for each beat is 1 joule. calculate the power of heart if it beats 72 times in a minute.          [3 Mark]
(b)The engine of train has yo apply a force of 5000 N to overcome friction to run at a uniform rate of 90 km/hr. What is the power developed by the engine?           [3 Mark]
(c)Differentiate between renewable and non-renewable form of energy resource.   [2 mark]

Section-B

Question-1 State the conditions in which force applied on a body does no work.         [2 Mark]
 (a) Derive formula of K.E.          [4 Mark]
(b) A 40 newton object is released from a height of 10 m. Just before it hits the ground. By which amount its kinetics energy decreased in joules.         [2 Mark]



(c) The kinetic energy of a body is 250J. Find work done to move a body of mass 20kg up-to a height of 5 m.        [4 Mark]
(d)  A 78-kg skydiver has a speed of 62 m/s at an altitude of 870 m above the ground.
i. Determine the kinetic energy possessed by the skydiver.
ii. Determine the potential energy possessed by the skydiver.
iii. Determine the total mechanical energy possessed by the skydiver.      [4 Mark]
Question-2
(a) Calculate the work done in lifting 100 kg of water through a vertical height of 5 m.   [2 Mark]
(c) What kind of energy transformation takes place when a body is dropped from a certain height?        [4 Mark]
Question-3
 (a) A jumper has a mass of 52 kg. She is moving with a speed of 2 m/s at a height of 54.6 meters above the ground. Determine the total mechanical energy of the jumper and work done to throw a shot put of weight 2.5 kg upto the height 20 m.         [4 Mark]
(b) Calculate the work done in lifting 200 kg of water through a vertical height of 6 m? [4 Mark]

Nomenclature of Hydrocarbons

                         ORGANIC CHEMISTRY                                                                           

Draw the complete structural formula and condensed molecular formula for each compound.

IUPAC Name	Complete Structural Formula	Condensed Formula
butane
2-methylhexane
3-ethyl-2-methylnonane
propene
4-methyl-2-heptene
ethyne
5,6-dimethyl-2-octyne
cyclopropane
1,3-diethylcyclohexane