In the equation of motion, x=at+bt2 the units of a and b are respectively (where x is in metres and t is in seconds)
The x and y coordinates of the particle at any time are x=5t−2t2 and y=10t respectively, where x and y are in meters and t in seconds. The acceleration of the particle at t=2 s is
A wave is represented by the equation y=7 sin(7πt−0.04πx+π3) x is in metres and t is in seconds. The speed of the wave is