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2 years ago

Why do you need friction to walk?

Physics

2 answers:

Goshia [24]2 years ago

5 0

Answer:

The force of friction is a necessary force which helps us to walk on ground. The friction is generated between the shoes and the road. We press the ground and as a reaction the ground pushes us forward. The force of friction between sole and ground provides the necessary grip which pushes us forward

Explanation:

Don't copy word for word if your sending as paragraph answer

Ludmilka [50]2 years ago

3 0

Friction can be a useful force because it prevents our shoes slipping on the pavement when we walk and stops car tyres skidding on the road. When you walk, friction is caused between the tread on shoes and the ground. This friction acts to grip the ground and prevent sliding. Sometimes we want to reduce friction.

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Boron coated with SiC (or Borsic) reinforced aluminum containing aligned 20 vol% fibers is an important high-temperature, lightw

Scilla [17]

Answer:

Option C is correct.

Modulus of elasticity of the composite perpendicular to the fibers = (12 × 10⁶) psi

Explanation:

For combination of materials, the properties (especially physical properties) of the resulting composite is a sum of the fractional contribution of each material thay makes up the composite.

In this composite,

The fibres = 20 vol%

Aluminium = 80 vol%

Modulus of elasticity of the composite

= [0.2 × E(fibres)] + [0.8 × E(Al)]

Modulus of elasticity of the fibers = E(fibres) = (55 × 10⁶) psi. =

Modulus of elasticity of aluminum = E(Al) = (10 × 10⁶) psi.

But modulus of elasticity of the composite perpendicular to the fibers is given in the expression.

[1 ÷ E(perpendicular)]

= [0.2 ÷ E(fibres)] + [0.8 ÷ E(Al)]

[1 ÷ E(perpendicular)]

= [0.2 ÷ (55 × 10⁶)] + [0.8 ÷ (10 × 10⁶)]

= (3.636 × 10⁻⁹) + (8.00 × 10⁻⁸)

= (8.3636 × 10⁻⁸)

E(perpendicular) = 1 ÷ (8.3636 × 10⁻⁸)

= 11,961,722.5 psi = (11.96 × 10⁶) psi

= (12 × 10⁶) psi

Hope this Helps!!!

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2 years ago

A bullet is fired straight up from a gun with a

Katena32 [7]

<span>v(4 seconds)= 300 m/s - 9.8 (m/s^2)(4s) = 260.8 m/s </span>, hope this helps:)

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2 years ago

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The robot arm is elevating and extending simultaneously. At a given instant, θ = 30°, ˙ θ = 10 deg / s = constant θ˙=10 deg/s=co

motikmotik

Explanation:

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