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2 years ago

12

A car is traveling south at a speed of 69 miles per hour and then begins traveling west but continues traveling at the same spee

d. Which of the following has changed?
A. velocity
B. gravity
C. mass
D. speed

1 answer:

alexandr1967 [171]2 years ago

8 0

Velocity
Because velocity is speed with direction. In this scenario, the speed has not changed, but the direction did.

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what is the main reason that attitudes are more often revealed in spoken rather than written language

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It's a combination of all those things. probably because we are taught from an early age to write in an academic fashion, giving balanced arguments and a conclusion. When speaking from the heart, there is no opposing argument nor is there a conclusion, just emotion.

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What is the mass moment of inertia of a 20kg sphere with a radius of 0.2m about a point on the sphere's perimeter

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Seema knows the mass of a basketball. What other information is needed to find the ball’s potential energy? the volume and heigh

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3 years ago

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ASTM A229 oil-tempered carbon steel is used for a helical coil spring. The spring is wound with D = 50 mm d = 10.0 mm, and a pit

horrorfan [7]

Answer

given,

D = 50 mm = 0.05 m

d = 10 mm = 0.01 m

Force to compress the spring

$F = \dfrac{d^4G\delta}{8D^3N}$

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$F = \dfrac{d^4G}{8D^3}\times 0.004$

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$\tau = \dfrac{8FDk_s}{\pi d^3}$

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= 442.6 Mpa

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now,

$\tau_s \leq 0.45 S_u$

$\tau_s \leq 0.45 \times 1300$

$\tau_s \leq 585\ Mpa$

since corrected stress is less than the $\tau_s$

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2 years ago

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nirvana33 [79]

Answer:

4 times greater

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<u>Step 1:</u> Calculate light-collecting area of a 20-meter telescope (A₁) by using area of a circle.

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Where d is the diameter of the circle = 20-m

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$A_{2} = \frac{\pi d^{2}}{4}$

Where d is the diameter of the circle = 10-m

$A_{2} = \frac{\pi (10^{2})}{4}$

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$= \frac{314.2 m^2}{78.55 m^2}$

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