Answer:
The decay constant is 1.21×10^-4/year
Explanation:
Decay constant = 0.693/half-life
Half-life = 5730 years
Decay constant = 0.693/5730 years = 1.21×10^-4/year
The frequency of light wave is 0.6*10^15 Hz.
The relation between the speed of light, frequency, and wavelength is given as
c=λν
Plugging the values in the above equation
3*10^8=5*10^(-7)*ν
ν=0.6*10^15 Hz.
Therefore the frequency of the light wave is 0.6*10^15 Hz.
Answer:
the f is 1.3 m
Explanation:
Given that
An object 2.0m is from the concave mirror
And, the image is 4.0m from the mirror
We need to find out the f
So,
u = -2 m
v = -4 m
1 ÷ f = 1 ÷ v + 1 ÷ u
= (-1 ÷ 4) + (-1 ÷ 2)
= -3 ÷4
f = -4 ÷ 3
= |1.3| m
Hence, the f is 1.3 m
The old sweet potatoes rootlings
Answer:
100 m
Explanation:
Arthur and Betty should be walking the same amount of time if they start walking at the same time and stop when they meet = t
Speed of Arthur = 3 m/s
Speed of Betty = 2 m/s
Distance = Speed × time
Distance covered by Arthur = 3t
Distance covered by Betty = 2t
The distance covered by both of them will be 100 m

The speed of dog is 5 m/s
Spot is running back and forth at 5 m/s for 20 seconds
In 20 seconds the distance covered by the dog is
