The net force is (40 Newtons) (down the road).
But 40 Newtons is not going to move a piano very enthusiastically.
The total mass of the things on the road is 60 + 13, which is 73kg.
mass • acceleration = F
73 x 0.9m/s^2 = 65.7N
F = 65.7 N
Answer:
19320 kg/m³
Explanation:
density: This can be defined as the ratio of the mass of a body to its volume. The S.I unit of Density is kg/m³.
The formula of density is given as,
D = m/v ......................... Equation 1.
Where D = Density of the gold, m = mass of the gold, v = volume of the gold.
Note: From Archimedes's Principle, the piece of gold displace an amount of water that is equal to it's volume.
Amount of water displace = 27.2 - 25 = 2.2 mL.
Given: m = 42.504 g = 0.042504 kg, v = 2.2 mL = (2.2/10⁶) m³ = 0.0000022 m³
Substitute into equation 1
D = 0.042504/0.0000022
D = 19320 kg/m³
Hence the density of the piece of gold = 19320 kg/m³
Answer:
I will specify a value of 0.009T for the alternator’s magnetic field
Explanation:
E_peak = 14 V
d = 10cm = 0.1m, so r = 0.1/2 =0.05m
N = 250 turns
f = 1200rpm = (1200rp/m x 1m/60sec) = 20 revolutions per second
At peak performance, peak voltage is given by the equation;
E_peak = NABω
Let's make the magnetic field B the subject;
B = E_peak/(NAω)
Now we know that ω = 2πf
Thus, ω = 2π x 20 revs/s = 125.664 revs/s.
Let's convert it to the standard unit which is rad/s.
1 rev/s = 6.283 rad/s
Thus, 125.664 revs/s = 125.664 x 6.283 = 789.55 rad/s
Area (A) = πr² = π x 0.05² = 0.007854 m²
Thus, plugging in the relevant values to get;
B = 14/[(250 x 0.007854 x 789.55)] = 0.009T
