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2 years ago

Which is an example of the gravitational force?

Physics

2 answers:

Evgesh-ka [11]2 years ago

7 0

1. A basketball was thrown in the air and falls to the ground

Sergeeva-Olga [200]2 years ago

6 0

Answer:

1.a basketball that was thrown in the air falls to the ground

Explanation:

1.a basketball that was thrown in the air falls to the ground

From newton law of universal gravitation, it state that a object of any mass will have the tendency to come down when throw to the atmosphere.

this is the reason why acceleration due to gravity of any object thrown up are always the same. Acceleration due to gravity on earth is 9.8 m/s2.

You might be interested in

What is the energy of light that must be absorbed by a hydrogen atom to transition an electron from n = 3 to n = 5?

alina1380 [7]

Answer:

The energy absorbed by a hydrogen atom is 1.549 X10⁻¹⁹ J

Explanation:

Using Bohr's equation; the energy absorbed by the hydrogen atom can be calculated as follows:

$\delta E = (\frac{1}{n_2{^2}} -\frac{1}{n_1^{2}})13.6eV$

When an electron moves from a lower energy level to a higher energy level, energy is absorbed by the atom.

Lower energy level (n₂) = 3

Higher energy level (n₁) = 5

1 eV = 1.602X10⁻¹⁹ C

$\delta E = (\frac{1}{3{^2}} -\frac{1}{5^{2}})13.6X1.602X10^{-19}$

ΔE = 1.549 X10⁻¹⁹J

The energy absorbed by a hydrogen atom to transition an electron from n = 3 to n = 5 is 1.549 X10⁻¹⁹ J

4 0

3 years ago

A 30-kg child sits at the top of a 3-meter slide. After sliding down, the child is traveling 4 m/s. How much PE does he start wi

Jobisdone [24]

At the top:

   Potential Energy = (mass) x (gravity) x (height)

   = (30 kg) x (9.8 m/s²) x (3 meters)

   = 882 joules

At the bottom:

   Kinetic Energy = (1/2) x (mass) x (speed)²

   = (1/2) x (30 kg) x (3 m/s)²

   = (15 kg) x (9 m²/s²)

   = 135 joules .

He had 882 joules of potential energy at the top,
but only 135 joules of kinetic energy at the bottom.

Friction stole (882 - 135) = 747 joules of his energy while he slid down.
The seat of his jeans must be pretty warm.

6 0

3 years ago

A BMX bicycle rider takes off from a ramp at a point 2.4 m above the ground. The ramp is angled at 40 degrees from the horizonta

adoni [48]

Answer:

The BMX lands 5.4 m from the end of the ramp.

Explanation:

Hi there!

The position of the BMX is given by the position vector "r":

r = (x0 + v0 · t · cos α, y0 + v0 · t · sin α + 1/2 · g · t²)

Where:

r = position vector at time t

x0 = initial horizontal position

v0 = initial velocity

α = jumping angle

y0 = initial vertical position

g = acceleration due to gravity (-9.8 m/s² considering the upward direction as positive)

Please, see the attached graphic for a better understanding of the situation. At final time, when the bicycle reaches the ground, the vector position will be "r final" (see figure). The y-component of the vector "r final" is - 2.4 m (placing the origin of the frame of reference at the jumping point). With that information, we can use the equation of the y-component of the vector "r" (see above) to calculate the time of flight. With that time, we can then obtain the x-component (rx in the figure) of the vector "r final". Then:

y = y0 + v0 · t · sin α + 1/2 · g · t²

-2.4 m = 0 m + 5.9 m/s · t · sin 40° - 1/2 · 9.8 m/s² · t²

0 = -4.9 m/s² · t² + 5.9 m/s · t · sin 40° + 2.4 m

Solving the quadratic equation:

t = 1.2 s

Now, we can calculate the x-component of the vector "r final" that is the horizontal distance traveled by the bicycle:

x = x0 + v0 · t · cos α

x = 0 m + 5.9 m/s · 1.2 s · cos 40°

x = 5.4 m

The BMX lands 5.4 m from the end of the ramp.

Have a nice day!