Explanation:
The horsepower (hp) is a unit in the foot-pound-second ( fps ) or English system, sometimes used to express the rate at which mechanical energy is expended. It was originally defined as 550 foot-pounds per second (ft-lb/s). A power level of 1 hp is approximately equivalent to 746 watt s (W) or 0.746 kilowatt s (kW).
Answer:

Explanation:
When the block is displaced by x units
F= spring force
two springs are connected parallel

Writing Newtons second law, F = ma


a= x" ( differentiating x w.r.t time twice)

this the standard form of equation of oscillation spring mass system
This is the differential equation, x'' means that double differentiation of x , i.e, x'' is acceleration
since, Period 
therefore,

Answer: 20.4m
Explanation:
Mass = 0.145kg
Initial velocity, Vi =20m/s
Initial kinetic energy K =1/2mv^2
Initial potential energy Ui = mgx = 0joules
: From conservation of energy,
Uf + Kf = Ui + Ki ( where f represent (final) )
Thus
mgXf + 0 = 0+1/2 mv^2
Xf = Vi^2/ 2g
= (20m/s) ^2/ 2(9.81m/s)^2
=20.4m
Universe contains billions and billions of stars, galaxies, planets, asteroids, comets and many more different type of bodies. These objects emit radiations of varied frequency. In order to study these different kind of objects, different kind of technology is required. There are different type of missions: some contain probes which land on the surface, some orbit the bodies etc. These are for solar system. Yet some are space observatories having detectors to study light from distant objects. Further, there are different detectors for different wavelengths of electromagnetic spectrum.
Straight down, even if the person is standing on a hill