A20 kg child is on a swing that hangs from 3.0-m-long chains. what is her maximum speed if she swings out to a 49 ∘ angle?

L = length of the chain = 3 m

θ = angle with the vertical = 49 deg

h = height gained

In triangle ABD

Cosθ = AB/AD

Cosθ = AB/L

AB = L Cosθ

BC = AC - AB = L - L Cosθ

so h =  L - L Cosθ

inserting the values

h =  (3) - (3) Cos49 = 1.032 m

v = maximum speed at the bottom of the swing

Using conservation of energy

kinetic energy at the bottom of the swing = potential energy at the maximum height

(0.5) m v² = mg h

v = sqrt(2gh)

v = sqrt(2 x 9.8 x 1.032)

v = 4.5 m/s

weather forecasts are done by collecting data about the current state of the atmosphere mainly the temperature, humidity and wind and using meteorology, to determine the atmosphere that evolves over time. the h and l mean the high and low pressure. the red strip is a warm front. the blue strip is a cold front. the blue and red strip is a stationary front. the purple strip is a occluded front.

explanation:

answer: 802.3 kilo joules of energy represents 191.75 kilo calorie of energy.

explanation:

energy released during combustion of one mole methane = 802.3 kilo joules

if 1 kilo joule = 0.239006   kilo calorie

then ,802.3 kilo joule will be = 802.30.239006 kilo calorie

802.3 kilo joule = 191.75 kilo calorie

hence, the energy in kilo calorie is 191.75 kilo calorie.