A ball is thrown straight up in the air and just before it lands it is travelling -47.5 m/s. How long was the ball in the air?

Imagine that the earth and the-moon have positive charges of the same magnitud. How big isäºthe charge necesary to produce an el

lions [1.4K]

Answer:

5.7 x 10^12 C

Explanation:

Let the charge on earth and moon is q.

mass of earth, Me = 5.972 x 10^24 kg

mass of moon, Mm = 7.35 x 10^22 kg

Let d be the distance between earth and moon.

the gravitational force between them is

$F_{g}=G\frac{M_{e} \times M_{m}}{d^{2}}$

The electrostatic force between them is

$F_{e}=\frac{Kq^{2}}{d^{2}}$

According to the question

1 % of Fg = Fe

$0.01 \times 6.67\times10^{-11}\frac{5.97 \times 10^{24}\times7.35 \times 10^{22}}{d^{2}}=9 \times 10^{9}\frac{q^{2}}{d^{2}}$

$2.927 \times 10^{35}=9 \times10^{9}q^{2}$

$3.25 \times 10^{25}=q^{2}$

q = 5.7 x 10^12 C

Thus, the charge on earth and the moon is 5.7 x 10^12 C.

6 0

2 years ago

A ball is dropped from a building taking 3sec to fall to the ground. Calculate:

GenaCL600 [577]

Answer:

Vf = 29.4 m/s

h = 44.1 m

Explanation:

Data:

Initial Velocity (Vo) = 0 m/s
Gravity (g) = 9.8 m/s²
Time (t) = 3 s
Final Velocity (Vf) = ?
Height (h) = ?

==================================================================

Final Velocity

Use formula:

Vf = g * t

Replace:

Vf = 9.8 m/s² * 3s

Multiply:

Vf = 29.4 m/s

==================================================================

Height

Use formula:

$\boxed{h=\frac{g*(t)^{2}}{2}}$

Replace:

$\boxed{h=\frac{9.8\frac{m}{s^{2}}*(3s)^{2}}{2}}$

Multiply time squared:

$\boxed{h=\frac{9.8\frac{m}{s^{2}}*9s^{2}}{2}}$

Simplify the s², and multiply in the numerator:

$\boxed{h=\frac{88.2m}{2}}$

It divides:

$\boxed{h=44.1\ m}$

What is the velocity when falling to the ground?

The final velocity is 29.4 meters per seconds.

How high is the building?

The height of the building is 44.1 meters.

3 0

2 years ago

A 5000 g toy car starts from rest and moves a distance of 300 cm in 3 s under the action of a single constant force. Determine t

sveticcg [70]

Answer:

3.33 N

Explanation:

First, find the acceleration.

Given:

Δx = 3 m

v₀ = 0 m/s

t = 3 s

Find: a

Δx = v₀ t + ½ at²

3 m = (0 m/s) (3 s) + ½ a (3 s)²

a = ⅔ m/s²

Use Newton's second law to find the force.

F = ma

F = (5 kg) (⅔ m/s²)

F ≈ 3.33 N

4 0

2 years ago

What H & N can friction produce?

Angelina_Jolie [31]

Friction produces heat hope this helps

5 0

2 years ago

An electron moves with velocity v⃗ =(5.8i−6.7j)×104m/s in a magnetic field B⃗ =(−0.81i+0.60j)T.

Minchanka [31]

Answer:

Fₓ = 0, $F_{y}$ = 0 and $F_{z}$ = - 3.115 10⁻¹⁵ N

Explanation:

The magnetic force given by the expression

F = q v xB

the bold are vectors, the easiest analytical way to determine this force in solving the determinant

$F = q \left[\begin{array}{ccc}i&j&k\\5.8&-6.7&0\\-0.81&0.6&0\end{array}\right] 10^{4}$

F = 1.6 10⁻¹⁵ [ i( 0-0) + j (0-0) + k^( 5.8 0.60 - 0.81 67) ]

F =i^0 + j^0 - k^ 3.115 10⁻¹⁵ N

Fₓ = 0

$F_{y}$ = 0

$F_{z}$ = - 3.115 10⁻¹⁵ N

6 0

3 years ago