ENGINEERING COLLEGE

Q1. A truck traveling at 40 mph is approaching a stop sign. At time ????0 and at a distance of 80ft, the truck begins to slow down by decelerating rate of 12 ft/sec2 . Will the truck be able to stop in time?

Answers

Answer 1
Answer:

Answer:

The truck will not stop in time. The truck passes the stop sign by about 63.41 ft before it stops.

Explanation:

The distance that the truck starts slowing down = 80 ft from the stop sign

Using equations of motion, we can calculate the distance it will take the truck to stop, then check of it is less than or more than 80 ft.

u = initial velocity of the truck = 40 mph = 58.667 ft/s

v = final velocity of the truck = 0 ft/s (since it comes to a stop eventually)

x = horizontal distance covered during the deceleration

a = Deceleration = -12 ft/s² (it'll have a negative sign, since it is negative acceleration

v² = u² + 2ax

0² = 58.667² + 2(-12)(x)

24x = 3441.816889

x = 143.41 ft

143.41 ft > 80 ft; hence, the truck will not stop in time. The truck passes the stop sign by about 63.41 ft before it stops.
Answer 2
Answer:

Corrected Question:

A truck traveling at 40 mph is approaching a stop sign. At time t₀ and at a distance of 80 ft, the truck begins to slow down by decelerating at 12 ft/s2, will the truck be able to stop in time?

Answer:

The truck will not be able to stop in time.

Explanation:

==> First lets convert all variables to SI units

1 mph = 0.45m/s

40mph = 40 miles per hour = 40 x 0.45 m/s

40mph = 18m/s

1 ft = 0.3048m

80 ft = 80 x 0.3048m

80 ft = 24.38m

Also;

12ft/s² = 12 x 0.3048m/s²

12ft/s² = 3.66m/s²

==> Now, consider one of the equations of motion as follows;

v² = u² + 2as               -----------------(i)

Where;

v = final velocity of motion

u = initial velocity of motion

a= acceleration/deceleration of motion

s = distance covered during motion

Using this equation, lets calculate the distance, s, covered during the acceleration;

We know that;

v = 0               [since the truck comes to a stop]

u = 40mph = 18m/s

a = -12ft/s² = -3.66m/s²    [the negative sign shows that the truck decelerates]

Substitute these values into equation (i) as follows;

0² = 18² + 2 (-3.66)s

0 = 324 - 7.32s

7.32s = 324

s = (324)/(7.32)

s = 44.26m

The distance from where the truck starts decelerating to where it eventually stops is 44.26m which is past the stop sign (which is at 80ft = 24.38m).  This means that the truck stops, 44.26m - 24.38m = 19.88m, after the stop sign. Therefore, the truck will not be able to stop in time.

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Answers

Answer:

Decrease to typical from utilizing lambda-decrease:  

The given lambda - math terms is, (λf.λx.f(f(fx)))(λy.y×3)2

The of taking the terms is significant in lambda - math,  

For the term, (λy, y×3)2, we can substitute the incentive to the capacity.  

Therefore apply beta-decrease on “(λy, y×3)2,“ will return 2 × 3 = 6  

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Select the true statements regarding rigid bars. a. A rigid bar can bend but does not change length.
b. A rigid bar does not bend regardless of the loads acting upon it.
c. A rigid bar deforms when experiencing applied loads.
d. A rigid bar is unable to translate or rotate about a support.
e. A rigid bar represents an object that does not experience deformation of any kind.

Answers

Answer:

option b and E are true

Explanation:

A lever is an example of a rigid bar that can rotate around a given point. In a rigid material, the existing distance does not change whenever any load is placed on it. In such a material, there can be no deformation whatsoever. Wit this explanation in mind:

option a is incorrect, given that we already learnt that no deformation of any kind happens in a rigid bar.

option b is true. A rigid bar remains unchanged regardless of the load that it carries.

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option e is true. A rigid bar would not experience any deformation whatsoever.

Which of the following was an effect of world war 2 on agricultural industry

Answers

Answer:

Option C..Farmers saught new technology to help with the workload

hope this helped you

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Answers

Answer:

(c)- Elastic modulus

Explanation:

  We know that in tensile test we measure the properties of the material like yield strength,ultimate tensile strength ,Poisson ratio.

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Answers

Answer:

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Explanation:

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1 ton capacity is a unit of air conditioning and refrigeration which  measure the capacity of air conditioning and refrigeration unit.

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Answers

Answer:

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Explanation:

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a) Calculating the line current:

P_(in) = √(3)VICos\alpha \n76.9 * 1000= √(3)*208*I*0.88\nI = (76.9*1000)/(√(3)*208*0.88 )\nI = 242.58 A

b) Calculating Reactive Power:

The reactive power can be calculated as:

Q = P tanα

where,

Q = Reactive power

P = Active Power

α = power factor angle

Since,

Cos\alpha =0.88\n\alpha =Cos^(-1)(0.88)\n\alpha=28.36

Therefore,

Q = 76.9 * tan (28.36)\nQ = 76.9 * (0.5397)\nQ = 41. 5 kVAr
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