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No expanded working has been attached for this question yet. The verified answer is Option A.

No expanded working has been attached for this question yet. The verified answer is Option B.

No expanded working has been attached for this question yet. The verified answer is Option B.

(a) Surface tension is the property of a liquid which makes its surface behave as though covered by an elastic skin. (b) Surface tension can be reduce by; (i) Addition of impurities e.g. soap, oil, alcohol etc. (ii) Heating the liquid.

Wt. in air = 0.25 N Wt.in water = 0.15 N Therefore, lost in wt. in water = Upthrust in water = 0.25 - 0.15 = 0.10 N. Wt. in paraffin oil = 0.17 N. .. loss in wt. in oil = upthrust in the oil = 0.25 - 0.17 = 0.08 Ratio of upthrust in oil to upthrust in water = \(\frac{0.08}{0.10}\) = \(\frac{8}{10}\) = \(\frac{4}{5}\) Or 4 : 5

Efficiency = M.A/V.R X 100/1 M.A = Load/Effort = 500/250 = 2 V.R. = radius of wheel/radius of axle = 0.4/0.1 = 4. therefore Efficiency = 2/4 x 100/1 = 50 %

Real depth = thickness of the glass block = 9cm. Refractive index of the glass material = 1.5 But Refractive index = Real depth/Apparent depth => 1.5 = 9/Apparent depth therefore Apparent depth = 9/1.5 = 6cm. therefore Apparent displacement of the Coin = 9.6 = 3cm

The function of the radiator of a motor car is to "collect" heat from the circulating water and radiate some out, but it is itself cooled by the fan adjacent to it. whose function is primarily based on convection

No expanded working has been attached for this question yet. The verified answer is Option A.

Wet glass: Water's ability to adhere to the glass can cause inaccuracies in readings due to meniscus formation and inconsistent surface tension.

if you blow dry air over the glass you blow away this extra water vapor, thereby decreasing the amount of water vapor entering the glass.

a)(i) Nuclear fission is a nuclear reaction in which a heavy nucleus is split into different lighter nuclei emitting neutrons with the release of a large amount of energy. (ii) Nuclear fusion is a nuclear reaction between two light nuclei at high temperatures formic a heavier nucleus with the release of a large amount of energy. (b)(i) Applications of atomic energy are: - for the production of nuclear weapons for warfare - in the generation of electric power - for health diagnosis and radiotherapy - to detect leakages. In underground pipes carrying oils or gases. (ii) Half life is the time required for radioactive substance to decay to half of its original quantity. (iii) T = \(\frac{0.693}{\lambda}\) (c)(i) \(^{226}_{88} X \) ---> \(^{222}_{88} Y + ^4_2He\) By the emission of \(\alpha\) the mass number of X decreases by 4 the atomic number by 2 to give daughter nucleus Y (ii) \(^{222}_{86} Y \) ---> \(^{222}_{87} Z + ^0_{-1} e\) By the emission of \(\beta\) particle the mass number of Y is unchanged while the atomic number of Y is unchanged while the atomic number is increased by 1. (iii) \(^{226}_{87} Z \) ---> \(^{222}_{87} Z + ^0_0\gamma\) By emission of \(\gamma\) radiation, the mass and atomic number of Z remain unchanged.

No expanded working has been attached for this question yet. The verified answer is Option A.

In a nuclear reaction, neutron is used as a bullet fired into 23592U, to trigger off nuclear chain reaction, which of course is controlled

The particle in the reaction is a neutron \(^{23}_{11}\)Na + \(^1_0\)n → \(^{20}_9\)F + \(^4_2\)He