2021 NECO PHYSICS ANSWERS

NECO PHYSICS ANSWERS

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PHYSICS OBJ

1-10: BCEDBECBAD

11-20: DEDCBEDCEA

21-30: DDAEBBCBBC

31-40: CEDBBCBEAE

41-50: BDEEDECCCD

51-60: BEECECDBCB

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(1a)

(i) A multimeter

(ii) Reads if there is short circuit in the electric circuit

(1b)

(i) A simple microscope uses one lens while a compound microscope uses two lens

(ii) A compound microscope produces a higher magnification than that of simple microscope

(1c)

Using M= ZIt

I = M/Zt

I = 450/3.30*10- *25*60

I = 909A

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(3a)

Range (R) is defined as the horizontal distance from the point of projection to the point where the projectile hits the projection plane again

(3b)

Time of flight: T= 2usin/g

sin = Tg/2u = 1.5*10/2*12

sin = 15/24 = 0.625

 = sin-(0.625)

 = 38.7

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(4a)

(i) Flying bullet

(ii) A moving car

(4b)

mgh = mc

 = gh/c = 10*108/4200

= 0.257C or 0.257K

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(5a)

Vaporization is the conversion of a substance from the liquid or solid phase into the gaseous (vapour) phase.

(5b)

(i) Deform

(ii) No change

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(6a)

A stationary wave is produced by a superposition of two waves of the frequency and amplitude which are exactly out of phase with each other

(6b)

Wavelength = 4/2.5 = 1.6m

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(8a)

Lost Volt refers to the amount of energy lost (in a battery, generally) to energy resistance of components. It is generally fairly negligible, but to calculate: V=IR

where I is the current and R is resistance.

(8b)

(i) Secondary cell last long and can be used over again and again.

(ii) A secondary cell is rechargeable meaning that the chemical reactions taking place in the cell are reversible and can be carried out in the opposite direction to charge the cell again.

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