Answer:
Date Significance Soviet Union Mission
August 21, 1957 First intercontinental ballistic missile (ICBM) R-7 Semyorka
October 4, 1957 First artificial satellite First signals from space Sputnik 1
November 3, 1957 First dog in orbit (Laika) Sputnik 2
January 31, 1958 First US satellite, detection of Van Allen radiation belts
Explanation:
Answer is: <span>a hill over which a wagon is pushed.
</span>For all chemical
reaction some energy is required and that energy is called activation
energy (<span>energy
that needs to be absorbed for a chemical reaction to start)<span>.
There are two types of reaction: endothermic
reaction (chemical reaction that absorbs more energy than it releases)
and exothermic reaction (chemical reaction that releases more energy than
it absorbs).
</span></span>R<span>eactions
occur faster with a catalyst because they require less activation energy.</span>
Answer:
4Hg+2O2=4HgO
four Mercury + four oxygen
THE DISTANCE IN TM SHOULD BE EQUAL TO 162 KM
Answer:
A long lever with the fulcrum as close as possible to the load
Explanation:
If F be the effort , W be the weight , L₁ be the distance of load from fulcrum and L₂ be the distance of effort from the fulcrum ,
Taking moment of force about the fulcrum , we have
W x L₁ = F x L₂
F = W x ( L₁ / L₂ )
F will be minimum when L₁ will be minimum .
Hence fulcrum should be as close as possible to the load.
