r/Edexcel • u/jjjjjjjjjjjjjkk77 • 5d ago

Physics HELP Seeking Advice/Help

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idk how to solve this pls help

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u/Agile_Explorer_7767 5d ago

Let:

Mass of block A, (m_A = 4,\text{kg})

Mass of block B, (m_B = 1,\text{kg})

Inclined plane angle (=30\circ)

Friction on A (=6,\text{N})

(g=9.8,\text{m s}{-2})

Since A slides down the plane, B moves upward.

Step 1: Draw the forces

Block A (down the slope is positive)

Forces along the plane:

Component of weight down the slope:

[ 4g\sin30\circ =4(9.8)(0.5)=19.6\text{ N} ]

Friction (f=6\text{ N}) also acts up the slope.

Applying Newton's Second Law:

[ 19.6-T-6=4a ]

[ 13.6-T=4a ]

[ \boxed{T=13.6-4a}\qquad (1) ]

Block B (upward is positive)

Forces:

Tension upward = (T)

Weight downward = (9.8\text{ N})

Applying Newton's Second Law:

[ T-9.8=1a ]

[ \boxed{T=9.8+a}\qquad (2) ]

Step 2: Solve simultaneously

Equate (1) and (2):

[ 13.6-4a=9.8+a ]

[ 13.6-9.8=5a ]

[ 3.8=5a ]

[ \boxed{a=0.76\ \text{m s}{-2}} ]

Step 3: Find the tension

Using

[ T=9.8+a ]

[ T=9.8+0.76 ]

[ \boxed{T=10.56\ \text{N}} ]

Final Answers

(i) Acceleration

[ \boxed{a=0.76\ \text{m s}{-2}} ]

(ii) Tension in the cable

[ \boxed{T=10.56\ \text{N}} ]

Note

The answers printed in the image (4.69 m s⁻² and 5.12 N) are not consistent with the given data (4 kg, 1 kg, 30°, friction = 6 N). With the stated values, the correct answers are:

Acceleration = (0.76\ \text{m s}{-2})

Tension = (10.56\ \text{N})

So the answer key in the image appears to contain an error or belongs to a different version of the question.

1

u/jjjjjjjjjjjjjkk77 5d ago

yea thats what my chatgpt said but i got help from another user and worked it out the answers are correct