Answer:
c. No. An equation may have consistent units but still be numerically invaid.
Explanation:
For an equation to be corrected, it should have consistent units and also be numerically correct.
Most equation are of the form;
(Actual quantity) = (dimensionless constant) × (dimensionally correct quantity)
From the above, without the dimensionless constant the equation would be numerically wrong.
For example; Kinetic energy equation.
KE = 0.5(mv^2)
Without the dimensionless constant '0.5' the equation would be dimensionally correct but numerically wrong.
Answer:
H_w = 2.129 m
Explanation:
given,
Width of the weir, B = 1.2 m
Depth of the upstream weir, y = 2.5 m
Discharge, Q = 0.5 m³/s
Weir coefficient, C_w = 1.84 m
Now, calculating the water head over the weir
now, level of weir on the channel
H_w = y - H
H_w = 2.5 - 0.371
H_w = 2.129 m
Height at which weir should place is equal to 2.129 m.
Answer: A while driving a car. It is unsafe
Answer:
Their number should increase
Explanation:
The photoelectric effect is a phenomenon that causes the ejection of electrons from that metal as light shined onto a metal surface. Only certain frequencies of light can cause the ejection of electrons. However, if the frequency of the incident light is too low then no electrons were ejected even if the intensity of the light was very high. If the frequency of the light was higher then electrons were able to be ejected from the metal surface even if the intensity of the light was very low.
According to the accepted wave theory, light of any frequency will cause electrons to be emitted. Kinetic energy emitted by the electrons depends upon the intensity of light.
According to the accepted wave theory, number of electrons being ejected by the metal should increase
