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3 years ago

9

A2 kg block is accelerating at the rate of 5 m/s² while being acted on by two forces. One of the forces equals 30 N, 0°. What ar

e the
magnitude and the direction of the other force?

1 answer:

Mademuasel [1]3 years ago

6 0

Answer:

20 [N], in the opposite direction of the first force.

Explanation:

We know that newton's second law stipulates that the sum of forces on a body must be equal to the product of mass by acceleration.

$SumF = m*a\\30 + F = 2*5\\F = 30 - (2*5)\\F = - 20 [N]$

The negative sign means that the other force acting on the body must be in the opposite direction to the force of 30 [N]

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A car stands from rest and attains a speed of 20 m/s in 10 s. What distance will it cover ?

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Answer:

100m

Explanation:

100m

s=ut+1/2at^2

s= unknown, u=0, a=2, t=10

s=0*10+1/2(2)(10)^2

s=1/2(2)(100)

s=1(100)

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3 years ago

If |v|= 11, |w|= 23, |v-w|= 30, find |v+w|

GenaCL600 [577]

Answer:

$|v+w|=20$

Explanation:

We are given that

|v|=11

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|v-w|=30

We have to find the value of |v+w|

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Using the formula

$(30)^2=(11)^2+(23)^2-2(11)(23)cos\theta$

$900=121+529-506cos\theta$

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$250=-506cos\theta$

$cos\theta=-\frac{250}{506}$

$|a+b|^2=|a|^2+|b|^2+2a\cdot bcos\theta$

Using the formula

$|v+w|^2=(11)^2+(23)^2+2(11)(23)\times (-\frac{250}{506})$

$|v+w|^2=400$

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3 years ago

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Answer:

The extent to which it would stretch is $\Delta L = 0.015 \ m$

Explanation:

From the question we are told that

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The area is $A = 0.500 mm^2 = \frac{0.500}{1 *10^6} = 0.500*10^6 \ m^2$

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The Young modulus is mathematically represented as

$Y = \frac{\sigma}{e}$

Where $\sigma$ is the stress which is mathematically represented as

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Substituting values

$\sigma = \frac{1500}{0.500*10^{-6}}$

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And e is the strain which is mathematically represented as

$e = \frac{\Delta L}{L }$

Where $\Delta L$ The extension of the steel string

Substituting these into the equation above

$Y = \frac{3.0*10^9}{\frac{\Delta L}{L} }$

Substituting values

$2.0 *10^{11} = \frac{3.0*10^9}{\frac{\Delta L}{L} }$

$\Delta L = \frac{3.0*10^9 * 1}{2.0 *10^{11}}$

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vladimir1956 [14]

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Explanation:

Given

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