Time and space are both relative
Answer:
Systematic error can be corrected using calibration of the measurement instrument, while random error can be corrected using an average measurement from a set of measurements.
Explanation:
Random errors lead to fluctuations around the true value as a result of difficulty taking measurements, whereas systematic errors lead to predictable and consistent departures from the true value due to problems with the calibration of your equipment.
Systematic error can be corrected, by calibration of the measurement instrument. Calibration is simply a procedure where the result of measurement recorded by an instrument is compared with the measurement result of a standard value.
Random error can be corrected using an average measurement from a set of measurements or by Increasing sample size.
Answer:
Force, |F| = 2100 N
Explanation:
It is given that,
Water from a fire hose is directed horizontally against at a rate of 50.0 kg/s, 
Initial speed, v = 42 m/s
The momentum is reduced to zero, final speed, v = 0
The relation between the force and the momentum is given by :
|F| = 2100 N
So, the magnitude of the force exerted on the wall is 2100 N. Hence, this is the required solution.
Answer:
C.when the nucleus decays
Explanation:
In chemical reactions, the outermost electrons of atoms are re-arranged somehow without the involvement of the nuclei of the participating atoms of the elements.
Nuclear reactions causes changes within the atomic nucleus. For every atomic nucleus, a specific neutron/proton ratio ensures stability. When the stability ratio differs an atom becomes unstable and splits into one or more other nuclei with the emission of small particles of matter. This is what radioactivity entails.
Answer:
a. negative
b. zero
Explanation:
work is the change in the energy of a system due to external forces
work is done when a force moves a load through a distance in the direction of the force
The work done by a force on a system is positive when the force and the force displacement point in the same direction and negative when they point in opposite directions
in the scenario we are considering in the question, the force (the hand) moves the block vertically upwards but the displacement of the block reduces (in the opposite direction) since it decelerates. as such the work done by gravity on the block is negative.
the work done on the block is zero if the system consists of the block and the earth because there is no gravitational force exerted on the system
