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a projectile is fired with velocity u making an angle theta with the horizontal. its kinetic energy at the highest |
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Answer» :A particle is FIRED with velocity u making an θ theta with the horizontal.We have to find kinetic energy of object at the highest point★ A body is SAID to be projectile if it is projected into space with some initial velocity and then it continues to move in a vertical PLANE such that its horizontal ACCELERATION is zero and vertical downward acceleration is equal to g.In projectile motion, the kinetic energy is maximum at the point of projection or at the point of reaching the ground and is minimum at the highest point.In projectile motion, velocity of object at the highest point of parabolic path is u cosθwhere u denotes initial velocity ➝ K = 1/2 mv²By SUBSTITUTING v = u cosθ➝ K = 1/2 m(u cosθ)²➝ K = 1/2 mu² cos²θ➝ K = Ko cos²θwhere Ko denotes kinetic energy of object at initial point of projection. |
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