The quantity t1/2=τ ln 2 is called the half-life of an exponential decay, where τ=rc is the time constant in an rc circuit. the current in a discharging rc circuit drops by half whenever t increases by t1/2. for a circuit with r=2.0 kω and c=5.0 μf, if the current is 6.0 ma at t=5.0 ms, at what time (in ms) will the current be 3.0 ma?

it breaks and dirupture other materials and other sencews from the bottom

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.

3. dark matter

empty space could also be a simple vacuum