Ok so this is simple projectile motion problem.
if we have an object falling in free fall it is subject to gravity of -9.80m/s^2
so it says it takes 6 sec to fall and we know initial velocity was zero so we know that h=vt+1/2gt^2 so we get h=0+1/2*9.80*6^2 = 176.4m
so solving for final speed we get KE=PE = 1/2mv^2=mgh = 1/2v^2=gh so
v=sqrt(2*g*h) = sqrt(2*9.8*176.4m) = 58.8m/s final speed when it hits the ground
hope this helps you! Thanks!!
Answer:A block rests on a horizontal, frictionless surface. A string is attached to the block, and is pulled with a force of 45.0 N at an…
Explanation:
Answer: Approximately 65% from what i have learnt.
Answer:
Difference in height = 7.5 cm
Explanation:
We are given;.
Height of ethyl alcohol;h2 = 20 cm = 0.2 m
Density of glycerin: ρ1 = 1260 kg/m³
Density of ethyl alcohol; ρ2 = 790 kg/m³
To get the difference in height, the pressure at the top of the open end must be equal to the pressure at the point where the liquids do not mix since both points will be at different levels after the pouring.
Thus;
P1 = P2
Formula for pressure is; P = ρgh
Thus;
ρ1 × g × h1 = ρ2 × g × h2
g will cancel out to give;
ρ1 × h1 = ρ2× h2
Making h1 the subject, we have;
h1 = (ρ2× h2)/ρ1
h1 = (790 × 0.2)/1260
h1 = 0.125 m
Difference in height will be;
Δh = h2 - h1
Δh = 0.2 - 0.125
Δh = 0.075 m = 7.5 cm
It be desirable to use an energy resource that does not produce greenhouse gases because it contribute to climate change
.
Option C
<u>Explanation:</u>
Greenhouse gases are the toxic gases that contribute to the "greenhouse effect". Greenhouse gases have the ability to absorb and emit some of the outgoing energy that is radiated by the Earth's surface, eventually causing the heat to get accumulated in the "lower atmosphere". It is always beneficial to use Renewable Energy sources such as Wind, solar and water which gives no harm to the environment and climate with no greenhouse gas emissions.
<u>For example:</u> If we have to generate electricity, there will be no greenhouse gas production at the beginning and a very less amount of production at the entire life cycle.