Answer:
Following entries can be regarded as numbers:
1.56e-9
1.9435
-4.99
Explanation:
According to the given rules, only "e" can be used for show power of 10. Furthermore, using space between numbers and including units (without justification) are not allowed. Under these rules let us consider each number given.
1) 1.56e-9
This satisfies all three conditions given above and hence, is a number. Simplified value is
2) 3.25E4
As we can only use "e" for exponents, use of "E" is wrong, therefore this entry cannot be considered as a number.
3) 2.54 m
Here a space and a unit "m" (meter - unit of length) is used and therefore this entry cannot be considered as a number.
4) 1.56 e-9
Here a space is used due to which this value is not declared a number.
5) 1.9435
This again satisfies all conditions and therefore is a number.
6) -4.99
This is also a number as the use of + or - sign is allowed.
7) 1.23 inches
Here a space and a unit "inches" (unit of length) is used again and therefore this entry is also not a number.
Answer:
13.2086 gallons
Explanation:
1 Liters =0.264172 gallons
s0,
50 Liters=(50 x 0.264172 )gallons
=13.2086 gallons
Answer
given,
mass of ball, m = 57.5 g = 0.0575 kg
velocity of ball northward,v = 26.7 m/s
mass of racket, M = 331 g = 0.331 Kg
velocity of the ball after collision,v' = 29.5 m/s
a) momentum of ball before collision
P₁ = m v
P₁ = 0.0575 x 26.7
P₁ = 1.535 kg.m/s
b) momentum of ball after collision
P₂ = m v'
P₂ = 0.0575 x (-29.5)
P₂ = -1.696 kg.m/s
c) change in momentum
Δ P = P₂ - P₁
Δ P = -1.696 -1.535
Δ P = -3.231 kg.m/s
d) using conservation of momentum
initial speed of racket = 0 m/s
M u + m v = Mu' + m v
M x 0 + 0.0575 x 26.7 = 0.331 x u' + 0.0575 x (-29.5)
0.331 u' = 3.232
u' = 9.76 m/s
change in velocity of the racket is equal to 9.76 m/s
Explanation:
Potential energy is the energy obtained by an object due to the position of an object. Whereas kinetic energy is the energy obtained by an object due to its motion.
For example, an ball is placed over a building of height h. Then steps followed to covert its potential energy into kinetic energy are as follows.
Step 1: When ball is at placed over a building of height h, then it has only potential energy and no kinetic energy.
Step 2: A man pushes the ball and it moves in the downward direction.
Step 3: When ball starts to move or fall it gains kinetic energy, that is potential energy now becomes equal to 0.
Similarly, on reaching the ground and after bouncing a few times when it stop moving then kinetic energy converts into potential energy.