The formula for getting the density of an object is
density = mass/volume = ρ = m/v
mass =42 kg
volume = 22m3
we will work on the equation directly because they are already in there SI units
density = 42 kg/22m3
density = 1.9090909090909
which if rounded can become 1.9 kg/m3
ans = the object's density is 1.9090909090909 kg/m3 or 1.9 kg/m3
Answer:
1.26m/s; 4.96m/s
Explanation
Acceleration is defined as the change I'm velocity of an object with respect to time.
Mathematically,
Acceleration (a) = change in velocity (v-u)/time (t)
Where v is the final velocity
u is the initial velocity
From the equation, it can be deduced that;
v = u+at
If the runner had an initial vertical velocity of -0.7 m/s over a period of 0.2seconds, its final velocity;
v = (-0.7)+9.81(0.2) (a=g=9.81m/s²)
v = -0.7+1.962
v = 1.26m/s
If the runner had an initial horizontal velocity of 3 m/s over a period of 0.2seconds, its final velocity;
v = 3+9.81(0.2)
v = 3+1.962
v = 4.96m/s
Answer:
so the exact time can be measured
Explanation:
if it is not used then let's say 2 athletes finish the race at the time 20 second so it won't be exact and you would not know who is first and if it is used then you even know how much or which part of the second it is, hope you understand . brainy plzz
Answer:
Mike will receive an electric shock
Explanation:
Human body is a conductor of electricity. When lightning strikes rod and give it negative charge, the rod will dissipate its charge as soon as it comes in contact with earth via conduting material. Mike will receive a severe electric shock as negatice charge pass through his body to other rod and to the ground.His body will feel numb. He may also get unconscious.