Answer:
5.0 × 10⁵
Explanation:
Quantity of charge Q = It
V= IR
I = V / R
Q = Vt/R
Q = ne
ne = Vt/R
n, number of K⁺ ions = Vt / Re
V = 80 × 10 ⁻³
t = 1 × 10⁻³ s
R = 1 × 10⁹ Ω
e = 1.6 × 10⁻¹⁶C
n, number of K⁺ ions = (80 × 10 ⁻³ V × 1 × 10⁻³ s ) / (1 × 10⁹ Ω × 1.6 × 10⁻¹⁹C) = 5.0 × 10⁵
Answer:
The answer to your question is: C. -9.81 m/s²
Explanation:
A. 9.81 m/s² acceleration is considered positive when it goes to the center of the earth, so this option is incorrect.
B. 0 m/s² This option is incorrect because acceleration is 0 for a linear motion without acceleration.
C. -9.81 m/s² If a projectile goes to the sky, then the acceleration will be negative.
D. It is not constant. Acceleration is constant.
Answer:
f = 485.62 N
Explanation:
Since, the bag is moving with some acceleration. Hence, the unbalanced force will be given as:
Unbalanced Force = Horizontal Component Applied Force - Frictional Force
Unbalanced Force = Fx - f
But, from Newtons Second Law of Motion:
Unbalanced Force = ma
comparing the equations:
ma = Fx - f
f = F Cos θ - ma
where,
f = frictional force = ?
F = Applied force = 593 N
m = mass of person = 49 kg
a = acceleration = 0.57 m/s²
θ = Angle with horizontal = 30°
Therefore,
f = (593 N)(Cos 30°) - (49 kg)(0.57 m/s²)
f = 513.55 N - 27.93 N
<u>f = 485.62 N</u>
Objects should be cooled before their mass is determined on a sensitive balance because it could damage the balance. Also, because it would give you wrong reading of the mass. Hot objects would warm the air around it. A warm air would expand and would produce convection as it rises causing to give the object a mass that is less than the actual. Another reason would be it would cause instability in the readings, the mass would fluctuate every now and then due to the convection currents around the object. It is always recommended to weigh the masses of objects that are in room temperature.
