Answer: Symbol A
Explanation:
The four symbols described here represent:
- Symbol A shows two dots and a line draw from one not connected to the other. --> this is an open switch. A switch is component of a circuit that is used to open/close the circuit in order to interrupt/allow the flow of current through the circuit. In this case, the switch is open, since the line does not connect the second dot.
- Symbol B shows two dots and a line draw from one connected to the other. --> this is the symbol used to represent the switch when it is closed, so it is a closed switch.
- Symbol C shows vertical lines in the pattern long, short, long, and short with a plus and minus symbol on it. --> this symbol represents a battery, which consists of two or more cells and provides the electromotive force that pushes the electrons along the circuit.
Therefore, the correct symbol representing the open switch is
Symbol A
Answer:
Light or visible light is electromagnetic radiation within the portion of the electromagnetic spectrum that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nm, or 4.00 × 10⁻⁷ to 7.00 × 10⁻⁷ m, between the infrared and the ultraviolet.
Explanation:
This is one type of light.
Answer:
a)- 1.799 rad/sec²
b)- 17.6 x 10ˉ³Nm
Explanation:
ω₀ = 720 rev/min x (1 min/60 sec) x (2π rad / 1 rev) = 24π rad/s
a) Assuming a constant angular acceleration, the formula will be
α = (ωf -ω₀) / t
As final state of the grindstone is at rest, so ωf =0
⇒ α = (0-24π) / 41.9 = - 1.799 rad/sec²
b)Moment of inertia I for a disk about its central axis
I = ½mr²
where m=2kg and radius 'r'= 0.099m
I = ½(2)(0.099²)
I = 9.8 x 10ˉ³ kgm²
Next is to determine the frictional torque exerted on the grindstone, that caused it to stop, applying the rotational equivalent of the Newton's 2nd law:
τ = I α =>(9.8 x 10ˉ³)(- 1.799)
τ = - 17.6 x 10ˉ³Nm
(The negative sign indicates that the frictional torque opposes to the rotation of the grindstone).
Answer:
0.58 days is needed
Explanation:
Gravitational energy change from a height change equal to 8848 m for a mass of 53 kg is:
m*g*h = 53*9.81*8848 = 4600340.64 J = 4600.34 kJ
4.184 kJ are equivalent to 1 kcal, then:
4.184 kJ / 4600.34 kJ = 1 kcal / x kcal
x = 4600.34/4.184
x = 1099.5 kcal or large calories
The diet is 1910 kcal/day, then you need 1099.5/1910 = 0.58 days
Answer:
The work done on the object by the force accelerating it is 520.31 J
Explanation:
Given;
mass of an object = 4.3 kg
horizontal velocity of the object, v = 11 m/s
time of acceleration, t = 3.4 s
work done is given as the product of force and distance
Work done = Fd
horizontal distance traveled by the object within 3.4 s, is calculated as follows;
X = Vt + ¹/₂gt², gravity has little or no influence on horizontal displacement, thus g = 0
X = Vt
X = 11*3.4 = 37.4 m
Force on the object, F = ma = m(v/t) = 4.3(11/3.4) = 13.912 N
work done = Fd = 13.912 x 37.4 = 520.31 J
Therefore, the work done on the object by the force accelerating it is 520.31 J
