Answer:
Weight
Explanation:
The spring balance is used to measure weight of an object.
D because gamma rays and ultra violet rays are one of the examples of the three ways to transfer heart which is convection, radiation, and conduction.
Kinetic energy of the rock just before it hits the ground=KE=33000 J
Explanation:
Weight= 2200N
mg=2200
m(9.8)=2200
m=224.5 kg
initial velocity=0
final velocity =V
using kinematic equation V²=Vi²+2gh
V²=0+2 (9.8)(15)
V=17.1 m/s
now kinetic energy= 1/2 mV²
KE= 1/2 (224.5)(17.1)²
KE=33000 J
Thus the kinetic energy of the rock just before it hits the ground=33000 J
Index of refraction of a substance =
(speed of light in vacuum) / (speed of light in the substance)
Index in quartz = (2.9979 x 10⁸ m/s) / (2.0567 x 10⁸ m/s)
<em>Index = 1.4576 </em> (no units)