Correct Answer: A. 340.0ms^-1

Correct Answer: D. \( 1.24 \times 10^{15}\)Hz

Explanation

h = \( 6.6 \times 10^{-34}\)Js, 1eV = \( 1.6 \times 10^{-19}\)J, \(E_1\) = - 8.6eV, \(E_2\) = - 3.5eV, f = ?

ΔE = hf

f = \(\frac{ΔE}{h}\)

ΔE = \(E_2\) - \(E_1\) = - 3.5eV - (- 8.6eV) = 5.1eV

but 5.1eV = 5.1 X \( 1.6 \times 10^{-19}\) = \( 8.16 \times 10^{-19}\)J

f = \(\frac{8.16 \times 10^{-19}}{ 6.6 \times 10^{-34}}\)

Therefore, f = \( 1.24 \times 10^{15}\)Hz

Correct Answer: C. Toward centre O

Explanation

Simple harmonic motion (SHM) is a special type of periodic motion where the restoring force on the moving object is directly proportional to the magnitude of the object's displacement and acts towards the object's equilibrium position.

Explanation

(a) (i) The angle of incidence in the optically denser medium for which the angle of refraction in the less dense medium is 90\(^o\)

(ii) Conditions necessary for total internal reflection to occur:

- Light rays must travel from a dense medium to a less dense medium.

- Angle of incidence in the dense medium must be greater than the critical angle.

iii) Practical applications of total internal reflection

- Prism periscopes.

- Prism Binoculars.

- Fibre optics

- Fish eye view.

- Transmission of radio signals

(b) Effects of refraction

- straight objects placed in liquid appear bent (on the interface or boundary)

- mirages.

- dispersion of white light/formation of rainbow.

- apparent displacement of objects placed in liquids/apparent shadows of pools base.

(c)(i) Definition of progressive waves: A disturbance which travels through a medium that enables energy to be transferred from its source to another (without the particles of the medium transferred). OR Transfer of energy and momentum from the source of disturbances.

(ii) (\(\alpha\)) calculation of frequency of wave

y = 0.5 sin (1000) \(\pi\) t - 100 \(\pi \frac{x}{17}\)

= a sin (2\(\pi ft - 2 \pi \frac{x}{\gamma}\))

= 2\(\pi f = 1000 \pi\)

f = 500Hz

(\(\beta\)) calculation of wavelength of wave

\(\frac{2\pi}{\lambda} = \frac{100\pi}{17}\)

\(\lambda\) = \(\frac{2 \times 17}{100}\)

= 0.34m

(\(\gamma\) calculation of speed of wave)

v = f\(\lambda\)

= 500 x 0.34

170ms\(^{-1}\)

Correct Answer: B. 2.46mm

Correct Answer: C. has both wave and particle properties

Correct Answer: B) density

Correct Answer: C. potential energy

Explanation

Examples of scalar quantities are mass, distance, charge, volume, time, speed, and the magnitude of physical vectors in general.

The moment of inertia is a scalar quantity.

Correct Answer: D) 2.50 x 103N

Correct Answer: D. 179^oC

Explanation

\(\alpha = \frac{L_2 - L_1}{L_1(\theta_2 - \theta_1)}\)

L\(_2\) - L\(_1\) = \(\alpha L_1 (\theta_2 - \theta_1)\)

\(\theta_2 = \frac{0.007}{2.3 \times 10^{-5} \times 1.8}\) + 10

= 179°C