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4 years ago

13

A car traveling 90 km/hr is 100 m behind a truck traveling 50 km/hr. How long will it take the car to reach the truck?

2 answers:

Ber [7]4 years ago

8 0

v = speed of car = 90 km/h

u = speed of truck = 50 km/h

d = initial separation distance = 100 m = 0.1 km

They meet at time t such that

vt = d + ut

t(v - u) = d

t = d/(v - u) = (0.1 km) / [(90 - 50) km/h] = 0.0025 hours

olganol [36]4 years ago

7 0

95t - .210 = 50t

95t - 50t = 0.210

45t = 0.210

t = 0.210/45

t = 0.0047 km/hr

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3 years ago

Parallel light rays with a wavelength of 563 nm fall on a single slit. On a screen 3.30 m away, the distance between the first d

MrMuchimi

Answer:

The width of the slit is 0.4 mm (0.00040 m).

Explanation:

From the Young's interference expression, we have;

(λ ÷ d) = (Δy ÷ D)

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3 years ago

A 60 cm diameter wheel accelerates from rest at a rate of 7 rad/s2. After the wheel has undergone 14 rotations, what is the radi

Mamont248 [21]

Answer:

$a=368.97\ m/s^2$

Explanation:

Given that,

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Let t is the time. Using second equation of kinematics can be calculated using time.

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Let $\omega_f$ is the final angular velocity and a is the radial component of acceleration.

$\omega_f=\omega_i+\alpha t\\\\\omega_f=0+7\times 5.01\\\\\omega_f=35.07\ rad/s$

Radial component of acceleration,

$a=\omega_f^2r\\\\a=(35.07)^2\times 0.3\\\\a=368.97\ m/s^2$

So, the required acceleration on the edge of the wheel is $368.97\ m/s^2$ .

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3 years ago

A closely wound search coil has an area of 3.13 cm2, 135 turns, and a resistance of 61.1 Ω. It is connected to a charge-measurin

erastovalidia [21]

Answer:

Explanation:

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charge through the coil = ∫ i dt

= ∫ dΦ /dt x 1/R dt

= 1 / R ∫ dΦ

= Φ / R

Total resistance R = 61.1 + 44.4 = 105.5 ohm .

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B = 3.44 x 10⁻⁵ x 105.5 / 422.55 x 10⁻⁴

= .86 x 10⁻¹

= .086 T .

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3 years ago

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jok3333 [9.3K]

Answer:

A

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3 years ago

Read 2 more answers