The correct answer is: Option (A) 75 J
Explanation:
First, be careful with the units here. As you can see it is mentioned that there is a 50N box. It means that the weight (<em>mg</em>) of the box is given as the unit is <em>Newton</em>, not its mass (which is in kg).
As,
Potential-energy = mass * acceleration-due-to-gravity * height
PE = m*g*h --- (A)
In equation (A), mg is actually the weight of the box, which is given.
mg = 50N
h = height = 1.5m
Plug the values in equation (A):
PE = 50 * 1.5 = <em>75 J (Option A)</em>
Answer:
reliability
accuracy
Explanation:
If a reading of a measurement is consistently the same then the measurement is reliable.
If a reading of measurement is close the actual value of the measurement then the reading is accurate.
Here, a stationary tree shows reading 6 mph once and 0 mph another instant. So, neither the reading of a measurement is consistent not the reading of measurement is close the actual value.
Hence, the radar has problems in its reliability and accuracy
Answer:
Albert Einstein
Explanation:
He first predicted the existence of black holes in 1916
Answer:0.69
Explanation:
Coefficient of kinetic friction=f/R=61.8/90=0.69
The Paleozoic era spanned from the Cambrian to the Permian and ended with a mass extinction at the end of the Permian. Geologists are still unsure of the cause but the theories include a meteorite impact or a massive volcanic event in Siberia or a combination of both. This could be a possible cause of the melting of the late Paleozoic ice sheets.
