Boron atoms are added to a si film resulting in an impurity density of 4 × 1016 cm–3. (a) what is the conductivity type (n-type or p-type) of this film? (b) what are the equilibrium electron and hole densities at 300 k and 600 k? (c) why does the mobile carrier concentration increase at high temperatures? (d) where is the fermi level located if t = 600 k?

the first american roller coaster was the mauch chunk switchback railway, built in the mountains of pennsylvania in the mid-1800s. the track, originally built to send coal to a railway, was reconfigured as a "scenic tour."

scientific laws are the result of testing theories and proving them to be facts.

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.

magnets not strong enough

explanation: