A ball is projected on smooth incline plane in direction perpendicular to line of greatest slope with velocity of 8 m/sec. Find it’s speed after 1 second

Let the ball be projected in the direction perpendicular to the line of greatest slope (i.e. the slope of the inclined plane itself). So The angle of projection θ can be taken as 0. Now the equations for the horizontal and vertical components of the velocity after time t are given byvx = u cos θ - g sin α x tvy = u sin θ + g cos α x tVelocity after time t = (vx2 + vy2)½If the angle of inclination α is known we can find v.