Motion Motion Physics makes models that approximate reality with math. Physics models have made amazing progress, but so far no model perfectly matches reality. x = 10.4 y = 3.8 Vx = 0.2 Vy = -0.8 This model approximates particle motion and collisions. It gives each particle a position and velocity. Every second, a particle’s …
Question1. Which of the following frequencies will be suitable for beyond-the-horizon communication using sky waves? (a) 10 kHz (b) 10 MHz (c) 1 GHz (d) 1000 GHz Solution : (b) 10 MHz For beyond-the-horizon communication, it is necessary for the signal waves to travel a large distance. 10 KHz signals cannot be radiated efficiently because …
Question1. In an n-type silicon, which of the following statement is true: (a) Electrons are majority carriers and trivalent atoms are the dopants. (b) Electrons are minority carriers and pentavalent atoms are the dopants. (c) Holes are minority carriers and pentavalent atoms are the dopants. (d) Holes are majority carriers and trivalent atoms are the …
Question1. (a) Two stable isotopes of lithium and have respective abundances of 7.5% and 92.5%. These isotopes have masses 6.01512 u and 7.01600 u, respectively. Find the atomic mass of lithium. (b) Boron has two stable isotopes, and. Their respective masses are 10.01294 u and 11.00931 u, and the atomic mass of boron is 10.811 u. Find the …
Question1. Choose the correct alternative from the clues given at the end of the each statement: (a) Size of an atom in Rutherford’s model is _________ the size of an atom compared to of Thomson’s model. (Less than, Greater than, no different than) (b) Even in the case of stable equilibrium _________ electrons experience a …
Question1. Find the (a) maximum frequency, and (b) minimum wavelength of X-rays produced by 30 kV electrons. Solution :Potential of the electrons, V = 30 kV = 3 × 104 V Hence, energy of the electrons, E = 3 × 104 eV Where, e = Charge on an electron = 1.6 × 10−19 C (a)Maximum frequency produced by …
CLASS 12 PHYSICS CHAPTER 11-DUAL NATURE OF RADIATION AND MATTER Read More »
Question1. Monochromatic light having a wavelength of 589nm from the air is incident on a water surface. Find the frequency, wavelength and speed of (i) reflected and (ii) refracted light? [1.33 is the Refractive index of water] Solution :Monochromatic light incident having wavelength, λ = 589 nm = 589 x 10-9 m Speed of light in …
Question1. A small candle, 2.5 cm in size is placed at 27 cm in front of a concave mirror of radius of curvature 36 cm. At what distance from the mirror should a screen be placed in order to obtain a sharp image? Describe the nature and size of the image. If the candle is …
CLASS 12 PHYSICS CHAPTER 9-RAY OPTICS AND OPTICAL INSTRUMENTS Read More »
Question1. Two circular plates having radius of 12 cm each and separated by 5 cm are used to make a capacitor as shown in the Figure 8.6. An external source charges this capacitor. 0.15 A is the charging current which remains constant. (a) Determine the capacitance and the rate of charge of potential difference between …
CLASS 12 PHYSICS CHAPTER 8-ELECTROMAGNETIC WAVES Read More »
Question1. A 100 Ω resistor is connected to a 220 V, 50 Hz ac supply. (a) What is the rms value of current in the circuit? (b) What is the net power consumed over a full cycle? Solution :Resistance of the resistor, R = 100 Ω Supply voltage, V = 220 V Frequency, ν = …