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Brut [27]
3 years ago
10

NEED HELP THIS IS DUE IN 30 MINUTES

Physics
1 answer:
11111nata11111 [884]3 years ago
8 0

-- The total distance between the towns = 460 km.

-- For the first 3 hours, he travels at an average speed of 60 km/hr.  During that time, he covers (60 km/hr) x (3 hrs) = 180 km.

-- At that point, he still has (460km - 180km) = 280 km to go.

-- If he drives that 280km at an average speed of 70 km/hr, it'll take him (280km)/(70km/hr) = 4 hrs to cover it.

-- His total time for the whole trip is (3 hours for the first part) + (4 hours for the last part) = <em>7 hours</em>.

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in which type of wave are vibrations at right angles to the direction in which the wave is travelling​
Pani-rosa [81]

Answer:

longitudinal waves have those properties

7 0
3 years ago
A 100 Kg man is diving off a 50 meter cliff. What is his kinetic energy when he is 20 meters from the water?
iren2701 [21]

Answer:

K.E=29.403125J

Explanation:

From the question we are told that

Mass M=100

Height 50-20=30m

Generally the equation for velocity before impact is is is mathematically given by

v=\sqrt{2gh}

v=\sqrt{2*9.8*30}

v=24.25

Generally the equation for Kinetic Energy is is mathematically given by

K.E=\frac{1}{2}mv^2

K.E=\frac{1}{2}*100*(24.25)^2\\

K.E=29403.125J

K.E=29.403125J

8 0
3 years ago
A ray of light travels across a liquid-to-glass interface. if the indices of refraction for the liquid and glass are, respective
prisoha [69]
When it comes to optics, Snell's law is the basic formula to be used. If you notice, when light hits the water, the light does not travel in the same direction. After, it hits the water, it changes in angle. Light becomes refracted. This is observed when your hands tend to become bigger if you place it underwater. The formula for Snell's Law is

n₁ sin θ₁ = n₂sin θ₂, where n is the index of refraction. This depends on the type of medium. For example, for air, n=1. The parameters θ₁ is the angle of incidence, and θ₂ is the angle of refraction. Critical angle is the incident angle needed so that the refract angle is 90°. So, modifying the equation:

n₁ sin θcrit = n₂sin 90°, since sin 90°=1,
sin θcrit = n₂/n₁
θcrit = sin ⁻¹ (n₂/n₁)

Since liquid comes first before glass, n₁=1.75 and n₂=1.52. Substituting,
θcrit = sin ⁻¹ (1.52/1.75)
θcrit = 60.29°

7 0
3 years ago
A water bottle contains 15.0 ounces of water. A person drinks 0.5 ounces per minute. How many hours will it take to drink all of
Mariana [72]
It would take 30 minutes

You would do 15.0 divided by 0.5
4 0
2 years ago
A painter stands a horizontal platform which has a mass of 20kg and is 5m long, the platform is suspended by two vertical ropes
Lerok [7]

Answer:

R = 715.4 N

L =  166.6 N

Explanation:

ASSUME the painter is standing right of center

Let L be the left rope tension

Let R be the right rope tension

Sum moments about the left end to zero. Assume CCW moment is positive

R[5] - 20(9.8)[5/2] - 70(9.8)[5/2 + 2] = 0

R = 715.4 N

Sum moments about the right end to zero

20(9.8)[5/2] + 70(9.8)[5/2 - 2] - L[5] = 0

L =  166.6 N

We can verify by summing vertical forces

116.6 + 715.4 - (70 + 20)(9.8) ?=? 0

                                             0 = 0  checks

If the assumption about which side of center the paint stood is incorrect, the only difference would be the values of L and R would be swapped.

5 0
3 years ago
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