A circular loop of radius R is placed in a uniform magnetic field  $B=2\sin \pi t$ Tesla as shown. Which of the following is incorrect?

Net force on the loop is zero at  $t=\frac{1}{2}\sec$

Force on  every element of the loop is radially inward at  $t=\frac{7}{4}\sec$

Net force on the loop is zero at  $t=\frac{3}{2}\sec$

Force on  every element of the loop is radially inward at  $t=\frac{5}{4}\sec$