Balls bouncing off a wall: impulse is along the normalदीवार से टकराती गेंदें: आवेग अभिलंब के अनुदिश

NCERT Fig 4.6 · interactive diagram

Parts and their functions

• Rigid wall (दृढ़ दीवार) — The ball pushes on it; by the third law the wall pushes back equally.
• Head-on: u in, u out (सीधी टक्कर: u अंदर, u बाहर) — Δpₓ = (−mu) − (mu) = −2mu. Impulse magnitude = 2mu, away from the wall.
• At 30°: only pₓ reverses (30° पर: केवल pₓ उलटता है) — pₓ: mu cos 30° → −mu cos 30°; p_y = −mu sin 30° is unchanged. Impulse = 2mu cos 30°, along −x.
• Angle with the normal 30° (अभिलंब से कोण 30°) — Angle of incidence = angle of reflection, since speed is unchanged.
• Impulse on the ball (गेंद पर आवेग) — Always normal to the wall. Ratio (a) : (b) = 2mu : 2mu cos 30° = 2/√3 ≈ 1.15. The force on the wall is opposite: normal, into the wall.

Original diagram drawn by Simple Learning Hub, based on NCERT Fig 4.6. Report a mistake