A model would be useful for a scientist because it allows prediction of what may happen without doing really the experiments. It saves time and money for the scientist. Also, it helps scientists in communicating their <span>scientific investigation to people.</span>
Question is not complete and the missing part is;
A coin of mass 0.0050 kg is placed on a horizontal disk at a distance of 0.14 m from the center. The disk rotates at a constant rate in a counterclockwise direction. The coin does not slip, and the time it takes for the coin to make a complete revolution is 1.5 s.
Answer:
0.828 m/s
Explanation:
Resolving vertically, we have;
Fn and Fg act vertically. Thus,
Fn - Fg = 0 - - - - eq(1)
Resolving horizontally, we have;
Ff = ma - - - - eq(2)
Now, Fn and Fg are both mg and both will cancel out in eq 1.
Leaving us with eq 2.
So, Ff = ma
Now, Frictional force: Ff = μmg where μ is coefficient of friction.
Also, a = v²/r
Where v is linear speed or velocity
Thus,
μmg = mv²/r
m will cancel out,
Thus, μg = v²/r
Making v the subject;
rμg = v²
v = √rμg
Plugging in the relevant values,
v = √0.14 x 0.5 x 9.8
v = √0.686
v = 0.828 m/s
The brakes on a 15,680 N car exert a stopping force of 640 N. The car's velocity changes from 20.0 m/s to 0 m/s.
Answer:
the answers, the correct one is A v= 22.5 m/s
Explanation:
We can solve this problem using the concepts of conservation of mechanical energy
Starting point. Lowest point of the trajectory
Em₀ = K = ½ m v₀²
Final point. When it is at a height of y = 20 m
= K + U = ½ m v² + mg y
how energy is conserved
Emo = Emf
½ m v₀² = ½ m v² + m g y
v² = v₀² + 2 g y
let's calculate
v²2 = 30 2 + 2 9.8 20
v² = 508
v²= ra 508
v² = 22.54 m / s
When checking the answers, the correct one is A
Data:
<span>Hooke represented mathematically his theory with the equation:
F = K * x
On what:
F (elastic force) = ?
K (elastic constant) = 3 N/cm
x (deformation or elongation of the elastic medium) = 2cm
Solving:
</span>



Answer:
<span>
C. 6 N</span>