So if a valid argument does have a false conclusion, it cannot have all true premises. Thus at least one premise must be false. ... If an invalid argument has all true premises, then the conclusion must be false. FALSE: It is possible for an invalid argument to have all true premises and a true conclusion.
Power is the rate of work done given by dividing work done by time.Efficiency is the ratio of work output to work input
power input= 100 watts
power output = x
efficiency= 0.8
thus 0.8 = x/100, therefore x = 80
power is given by energy times time
hence time = 80/300000 = 0.00026 seconds
Time in hours = 0.00026/360 = 7.407 x 10 ∧7 hours
Answer:
Statement:
The electric current passing through a conductor is directly proportional to the potential difference across its ends provided temperature and other physical conditions remain constant.
Explanation:
Current is directly proportional to voltage loss through a resistor. That is, if the current doubles, then so does the voltage. To make a current flow through a resistance there must be a voltage across that resistance. Ohm's Law shows the relationship between the voltage (V), current (I) and resistance (R).
V∝I or I∝V⇒V=IR.
Answer:
t = 0.319 s
Explanation:
With the sudden movement of the athlete a pulse is formed that takes time to move along the rope, the speed of the rope is given by
v = √T/λ
Linear density is
λ = m / L
λ = 4/20
λ = 0.2 kg / m
The tension in the rope is equal to the athlete's weight, suppose it has a mass of m = 80 kg
T = W = mg
T = 80 9.8
T = 784 N
The pulse rate is
v = √(784 / 0.2)
v = 62.6 m / s
The time it takes to reach the hook can be searched with kinematics
v = x / t
t = x / v
t = 20 / 62.6
t = 0.319 s
