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2 years ago

13

một vật được ném từ đỉnh toàn nhà cao 20m so với mặt đát với vận tốc ban đàu 12m/s hợp với phương ngang một góc 30 độ. tính khoả

ng cách từ vị trí vật chạm đất đến chân tòa nhà (gốc O)

1 answer:

Helga [31]2 years ago

5 0

Sorry don't know which language is this can't understand O_o

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A ball is falling after rolling off a tall roof<br> The ball has what type of energy.

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Answer:

Linear and rotational Kinetic Energy + Gravitational potential energy

Explanation:

The ball rolls off a tall roof and starts falling.

Let us first consider the potential energy or more specifically gravitational potential energy ( $mgh$ ; $m$ = mass of the ball, $g$ = acceleration due to gravity, $h$ = height of the roof). This energy comes because someone or something had to do work to take the ball to the top of the roof against the force of gravity. The potential energy is naturally maximum at the top and minimum when the ball finally reaches the ground.

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3 years ago

A 2.0-kg laptop sits on the horizontal surface of the seat of a car moving at 8.0 m/s. The driver starts slowing down to stop. F

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Explanation:

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mass of laptop m=2 kg

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As the car is moving, so the coefficient of kinetic friction comes into play

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2 years ago

Air conditioners operate on the same principle as refrigerators. Consider an air conditioner that has 7.00 kg of refrigerant flo

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Answer:

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So we find mass of vapour at inlet generator

M1 = ( 1-0.54)*7= 3.2kg

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M2= 0.95*7= 6.7kg

So the Mass of vapour at exit generator is

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3 years ago

An electron initially has a speed 16 km/s along the x-direction and enters an electric field of strength 27 mV/m that points in

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Answer:

a) $t=1.4\times 10^{-5}\ s$

b)S= 46.4 cm

Explanation:

Given that

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V= 16,000 m/s

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b)

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Here initial velocity u= 0 m/s

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