Answer: B
Explanation:
An unbalanced force (net force) acting on an object changes its speed and/or direction of motion. An unbalanced force is an unopposed force that causes a change in motion.
Answer:
D By looking all the way to the cosmological horizon, we can see the actual conditions that prevailed all the way back to the first instant of the Big Bang.
Explanation:
Astrophysicists are able to determine the conditions that existed in the early universe, by using instruments such as telescopes to observe and study cosmic horizons. More ideas about the early universe can be found from the thermal light present in cosmic backgrounds.
Scientists study these details that provide an insight into the conditions that existed so many years ago. They have been able to determine that the Big Bang involved so many collisions from these observations.
Given
initial position = Xi= 19.9m
Final position Xf = 5.4m
Average velocity= Va = -0.418m/s
it shows displacement is reverse.
To find t=?
As Va = (Xf- Xi) / t
t = (Xf-Xi) / ( Va)
t = ( 5.4-19.9) / (-0.418)
t = (-14.5 ) / (-0.418) (-ve sign cancel out at numerator and denominator)
t =34.69 s
A) work = force * distance
mass is not a force, weight is, so we have to find the weight of the block.
Weight = mg
Weight = (220kg)(9.8)
Weight = 2156N
Work = 2156N * 3.10m
work = 6683.6J
b) Since he is holding the weights, it's not moving, therefore, he doesn't do any work
c) The answer is still the same amount of work when he lifted them.
d) The answer is no since when he let go the weight, he doesn't apply any force to the weight.
e) P = work/time
P = 6683.6J / 2.1s
P = 3182.67 watts
