Answer:
6 days.
Explanation:
From radioactivity, The expression for half life is given as,
R/R' = 2⁽ᵃ/ᵇ)................... Equation 1
Where R = original mass of the radioactive substance, R' = Remaining mass of the radioactive substance after decay, a = Total time taken to decay, b = half life.
Given: R = 80 g, R' = 10 g, b = 2 days.
Substitute into equation 1
80/10 = 2⁽ᵃ/²⁾
8 = 2⁽ᵃ/²⁾
2³ = 2⁽ᵃ/²)
Equating the base and solving for a
3 = a/2
a = 2×3
a = 6 days.
The instant it was dropped, the ball had zero speed.
After falling for 1 second, its speed was 9.8 m/s straight down (gravity).
Its AVERAGE speed for that 1 second was (1/2) (0 + 9.8) = 4.9 m/s.
Falling for 1 second at an average speed of 4.9 m/s, is covered <em>4.9 meters</em>.
ANYTHING you drop does that, if air resistance doesn't hold it back.
Explanation:
Given Data:
mass of dog = 12 Kg
dog's center of mass = 0.20m
length of dog = 0.50m
height of dog's jump = ?
Solution:
Work done of gravitational force = Gain in Potential energy
2.1 × mgΔh = mg (h - 0.1)
2.1 × (0.3 - 0.1) = (h - 0.1)
h = 0.52 m
Answer:
22/0.50=44
Explanation:
average speed= distance / time
Lines of Force around an Electromagnet. ... The magnetic field strength of an electromagnet is therefore determined by the ampere turns of the coil with the more turns of wire in the coil the greater will be the strength of the magnetic field.
