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A body lost in a jungle finds a note. In...

A body lost in a jungle finds a note. In the note was written the following things.
Displacements
1. 300 m `53^(@)` South of East .
2. 400 m `37^(@)` North of East
3. 500 m North
4. `500sqrt(2) m ` North- West
5. 500 m South
He starts walking at constant speed 2m/s following these displacements in the given order.
How far and in which direction is he from the starting ponit after 5 min. and 50 s ?

A

500 m due East

B

500 m due West

C

700 m due South- West

D

700 m due North-East

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we will follow these steps: ### Step 1: Understand the Displacements We have five displacements to consider: 1. **300 m South of East at 53°** 2. **400 m North of East at 37°** 3. **500 m North** 4. **500√2 m North-West** 5. **500 m South** ### Step 2: Break Down Each Displacement into Components We will resolve each displacement into its x (East-West) and y (North-South) components. 1. **For 300 m South of East at 53°:** - \( x_1 = 300 \cos(53°) \) - \( y_1 = -300 \sin(53°) \) 2. **For 400 m North of East at 37°:** - \( x_2 = 400 \cos(37°) \) - \( y_2 = 400 \sin(37°) \) 3. **For 500 m North:** - \( x_3 = 0 \) - \( y_3 = 500 \) 4. **For 500√2 m North-West:** - North-West means 45° from both North and West, so: - \( x_4 = -500 \) (since it goes West) - \( y_4 = 500 \) (since it goes North) 5. **For 500 m South:** - \( x_5 = 0 \) - \( y_5 = -500 \) ### Step 3: Calculate the Total Components Now we sum up all the x and y components. - Total x-component: \[ X = x_1 + x_2 + x_3 + x_4 + x_5 \] - Total y-component: \[ Y = y_1 + y_2 + y_3 + y_4 + y_5 \] ### Step 4: Calculate the Individual Components Using approximate values for trigonometric functions: - \( \cos(53°) \approx 0.6 \), \( \sin(53°) \approx 0.8 \) - \( \cos(37°) \approx 0.8 \), \( \sin(37°) \approx 0.6 \) Calculating each component: 1. \( x_1 = 300 \times 0.6 = 180 \) m, \( y_1 = -300 \times 0.8 = -240 \) m 2. \( x_2 = 400 \times 0.8 = 320 \) m, \( y_2 = 400 \times 0.6 = 240 \) m 3. \( x_3 = 0 \), \( y_3 = 500 \) 4. \( x_4 = -500 \), \( y_4 = 500 \) 5. \( x_5 = 0 \), \( y_5 = -500 \) ### Step 5: Sum the Components Total x-component: \[ X = 180 + 320 + 0 - 500 + 0 = 0 \text{ m} \] Total y-component: \[ Y = -240 + 240 + 500 + 500 - 500 = 500 \text{ m} \] ### Step 6: Calculate the Resultant Displacement The resultant displacement from the starting point is: \[ R = \sqrt{X^2 + Y^2} = \sqrt{0^2 + 500^2} = 500 \text{ m} \] ### Step 7: Determine the Direction Since the total x-component is 0 and the total y-component is positive, the direction is directly North. ### Final Answer The body is **500 m North** from the starting point. ---
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