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Ch 11: Impulse and Momentum
Knight Calc - Physics for Scientists and Engineers 5th Edition
Knight Calc5th EditionPhysics for Scientists and EngineersISBN: 9780137344796당신이 사용하는 게 아니라요?교과서 변경
11장, 문제 33b

At the center of a 50-m-diameter circular ice rink, a 75 kg skater traveling north at 2.5 m/s collides with and holds on to a 60 kg skater who had been heading west at 3.5 m/s. Where will they reach it? Give your answer as an angle north of west.

검증된 단계별 안내
1
Step 1: Recognize that this is a problem involving conservation of momentum. Since the skaters collide and stick together, it is an example of an inelastic collision. Momentum is conserved in both the north-south and east-west directions.
Step 2: Write the equation for conservation of momentum in the north-south direction. The momentum before the collision is given by the mass of the first skater multiplied by their velocity. After the collision, the combined mass of the two skaters moves with a final velocity in the north-south direction. Use the formula: py=m1v1.
Step 3: Write the equation for conservation of momentum in the east-west direction. The momentum before the collision is given by the mass of the second skater multiplied by their velocity. After the collision, the combined mass of the two skaters moves with a final velocity in the east-west direction. Use the formula: px=m2v2.
Step 4: Combine the momentum components to find the resultant velocity vector. Use the Pythagorean theorem to calculate the magnitude of the final velocity: v=vx2+vy2.
Step 5: Determine the direction of the final velocity vector. Use the tangent function to calculate the angle north of west: θ=tan⁡(vyvx). This angle gives the direction of the combined skaters' motion relative to the west direction.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
12m

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Conservation of Momentum

The conservation of momentum states that in a closed system, the total momentum before an event must equal the total momentum after the event. In this scenario, the skaters collide and hold onto each other, meaning we can calculate their combined momentum in both the north-south and east-west directions to find their final velocity after the collision.
추천 영상:
가이드 코스
05:58
Conservation Of Momentum

Vector Addition

Vector addition is the process of combining two or more vectors to determine a resultant vector. In this case, the velocities of the two skaters must be treated as vectors, taking into account their directions. The resultant vector will help determine the final direction and speed of the combined skaters after the collision.
추천 영상:
가이드 코스
07:30
Vector Addition By Components

Angle Measurement in Navigation

In navigation, angles are often measured relative to cardinal directions, such as north and west. To express the final direction of the skaters after the collision, we need to calculate the angle north of west, which involves using trigonometric functions to find the angle based on the resultant vector's components.
추천 영상:
가이드 코스
07:49
Proper Frames and Measurements
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