Why does a phonograph - record attract dust partiules just after it is cleaned?

Why does a phonograph record attract dust particles just after it is cleaned?

Why does a comb rubbed on hair attract small pieces of paper?

Dust particles released by comets are continuously acted upon by sun's radiation pressure in radial outward direction. Assuming a dust particle with rho =3.5 xx10^3 kg//m^3 and reflection coefficient 0. for what value of radius r does gravitational force on dust. particle just balance the radiation force on it from sunlight ? (power radiated by sun =4xx10^(26) W , mass of sun =2xx10^(30)kg )

A particle of mass m is kept on the top of a smooth sphere of radius R. It is given a sharp impulse which imparts it a horizontal speed v. [a]. find the normal force between the sphere and the particle just after the impulse. [B]. What should be the minimum value of v for which the particle does not slip on the sphere?[ c]. Assuming the velocity v to be half the minimum calculated in part, [d]. find the angle made by the radius through the particle with the vertical when it leaves the sphere.

Why does leather get hardened after tanning?

Why does a football come to a stop after rolling for some time?

Why does growth rate decrease after the exponential increase ?

Why does the electric fan continue to rotate for some time after the current is switched off ?

(a) what is the rate at which energy being delivered to a light bulb higher : just after it is turned on , the glow of the filament is increasing , or after it has been on for a few seconds and the glow is steady ? (b) IF a piece of wire is used to connect points b and c in Fig. 7.9, does the brightness of bulb R_(1) increase , decrease or stay constant ? What happens to the brightness of bulb R_(2) ? (I_(1) = I_(2) = I) (c) Compare the brightness of four identical light bulbs in Fig. 7.10 . What happens if the bulb A fails so that it cannot conduct ? What if C fails ? What if D fails? (d) If electric power is transmitted over long distances, the resistance of the wires becomes significant. Why ? Which mode of transmission would result in less energy losss: high current and low voltage or low current and high voltage ? Discuss. (e) In Fig. 7.11 , describe wha happens to the light bulb after the switch is closed . Assume the capacitor has a large capacitance and is initially uncharged. (f) Astuident claims that a second light bulb in series is less bright than the first , because the first bulb uses up some of the current . How would you respond to this statement ? (g) If you were to design an electeric heater using nichrome wire as the heating element , what parameters of the wire would you vary to meet a specific power output , sch as 1000 W ?

Why do people suffer from altitude sickness after reaching the high altitude regions ? How does their body acclimatized after a couple of days ?