Answer:
It can be said to be reliable although it is not valid
Explanation:
This is because Reliability means an indicator of consistency, A measure should produce similar or the same results consistently if it measures the same quantity. So does the thermometer measures over 5days but it is not valid because it deviates from the real value
Answer:
M.A = load/ effort
1200N/400N
= 3
velocity ratio= radius of wheel/radius of Axle
40cm/10cm
=4
efficiency= 3/4*100
75%
Objects are known to go down because of a unbalanced force
Answer:
Correct answer: E total = 2,800 J
Explanation:
Given:
m = 4 kg the mass of the object
V = 20 m/s the speed (velocity) of the object
H = 50 m the height of the object above the surface
E total = ? J
The total energy of an object is equal to the sum of potential and kinetic energy
E total = Ep + Ek
Ep = m g H we take g = 10 m/s²
Ep = 4 · 10 · 50 = 2,000 J
Ek = m V² / 2
Ek = 4 · 20² / 2 = 2 · 400 = 800 J
E total = 2,000 + 800 = 2,800 J
E total = 2,800 J
God is with you!!!
