In a hydrogen atom, the distance between the electron and proton is $2.5 \times {10^{ - 11}}\,m$. The electrical force of attraction between them will be
$2.8 \times {10^{ - 7}}\,N$
$3.7 \times {10^{ - 7}}N$
$6.2 \times {10^{ - 7}}N$
$9.1 \times {10^{ - 7}}N$
Which of the following sets of concurrent forces may be in equilibrium
An iron sphere weighing $10\, N$ rests in a $V$ shaped smooth trough whose sides form an angle of $60^o$ as shown in the figure. Then the reaction forces are
Inside a horizontally moving box, an experimenter finds that when an object is placed on a smooth horizontal table and is released, it moves with an acceleration of $10\,m / s ^2$. In this box if $1\,kg$ body is suspended with a light string, the tension in the string in equilibrium position (w.r.t. experimenter) will be$.........\,N$ (Take $g =10\,m / s ^2$ )
Write condition of equilibrium when three force act on a particle.
When body is at rest or it is in uniform motion, no force act on it.