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ahrayia [7]
2 years ago
7

The block brake consists of a pin-connected lever and friction block at B. The coefficient of static friction between the wheel

and the lever is μs = 0.3, and a torque of 5 N⋅m is applied to the wheel. Determine if the brake can hold the wheel stationary when the force applied to the lever is (a) P = 30 N, (b) P = 70 N.
Physics
2 answers:
ANTONII [103]2 years ago
7 0

Answer:

B

Explanation:

Nina [5.8K]2 years ago
7 0

Answer:

a) Insufficient

b) Sufficient

Explanation:

To hold lever:

Sum of moments about point O center of wheel = 0

Fb * 0.15 - 5 =0

Fb = 33.33N

Contact force Nb:

Nb = (Fb/u) = (33.333 / 0.3) = 111.1 N

Sum of moments about point A lever pin joint = 0

Preq * 0.6 - 111.1*0.2 - 33.33*0.05 = 0

Preq = 39.8 N

part a

P = 30N < Preq = 39.8N

Hence, insufficient

part b

P = 70N > Preq = 39.8N

Hence, sufficient

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Answer:

75 kgm/s

Explanation:

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From the question,

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Substitute into equation 1

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2 years ago
89. An electron is moving in a straight line with a velocity of 4.0×105 m/s. It enters a region 5.0 cm long where it undergoes a
ddd [48]

Explanation:

Given that,

Initial speed of the electron, u=4\times 10^5\ m/s

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v=8.71\times 10^5\ m/s

(b) Let t is the time for which the electron take to cross the region. It can be calculated as:

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Jules is conducting an experiment involving friction. He is measuring the temperature of various objects and surfaces after quic
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The incorrect prediction:

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Frances drew a diagram to show electromagnetic induction.
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I chose it and I got it right

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When a car accelerates from a standing start, the crash test dummy appears to be pressed backward into the seat cushion. Which o
Setler [38]

<u>Answer:</u>

Option: D. Gravity is pulling the crash test dummy in the direction the car is moving.

<u>Explanation: </u>

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