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Natali [406]
3 years ago
7

A projectile is shot horizontally at 23.4 m/s from the roof of a building 55.0 m tall. What is the time necessary for the projec

tile to reach the ground below?
Physics
1 answer:
baherus [9]3 years ago
5 0
The horizontal speed has no effect on the answer. 

It doesn't matter whether you flick a marble horizontally from the roof,
fire a high-power rifle horizontally from the roof, drive a school bus straight
off the roof, or drop a bowling ball from the roof with zero horizontal speed. 
Their vertical speed is completely determined by gravity, (and it happens to
be the same for all of them).

Handy dandy formula for the distance covered by anything that starts out
with zero speed and accelerates to the end:

            Distance = (1/2) (acceleration) x (time)²

If the beginning of the journey is on Earth, then the acceleration is
9.8 m/s² ... the acceleration of gravity on Earth.  We'll assume that
the 55-meter rooftop in the question is part of a building on Earth.

                       55 meters  =  (1/2) (9.8 m/s²) x (time)²           

Divide each side
by  4.9 m/s² :            55 m / 4.9 m/s²  =  (time)²

                                 (time)²  =  (55/4.9)  sec²

Square-root
each side:                time  =  √(55/4.9 sec²)

                                           =      3.35 sec  .
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Answer:

Explanation:

1 ) the volume of helium in the balloon when fully inflated

= 4/3 π R³

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= 623.3 m³

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6 0
3 years ago
What is the potential energy of a 2500 g object suspended 5 kg above the earth's surface?
Alinara [238K]

Answer:

potential \: energy = mgh \\  = ( \frac{2500}{1000} ) \times 10 \times 5 \\  = 125 \: newtons

if height is 5 m

8 0
3 years ago
A rock hits a window and stops in 0.15 seconds. The net force on the rock is 58N during the collision. What is the magnitude of
nlexa [21]

Answer:

The change in momentum is  \Delta p =   0.7 \ kg\cdot m \cdot s^{-1}

Explanation:

From the question we are told that

    The time taken for the stone to stop is \Delta  t = 0.15 \ seconds

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Substituting values

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       \Delta p =  I  =  0.7 \ kg\cdot m \cdot s^{-1}

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3 years ago
The steps in the heating of a metal seat in a park are listed below: Step 1: Heat travels from the sun to Earth Step 2: Heat tra
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The steps in the heating of a metal seat in a park are:

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-- From the top of the seat to the bottom, heat is transferred by conduction.  

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3 0
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