Muscle contracts and shortens at constant rate of speed, usually requires special, expensive equipment that increases the load as it senses that the muscle contraction is speeding up. *

This given statement is about "Isotonic Contraction".

Explanation:

There are basically two types of muscle contraction named as Isotonic and Isometric contraction.The variations of length of muscles take place when muscular contraction is against resistance then termed as "Isotonic contractions".

This retains constant muscle tension, as the length of the muscle varies.This can only occur when the average contraction force of a muscle is greater than the total load on the muscle.

Isotonic movements are either intense, which means shortening the working muscle, or eccentric, which means lengthening the working muscle. Isometric contraction involving muscle contraction to stress, in which the muscle length stays the same.

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s

the aurora is formed when charged particles emitted from the sun during a solar flare penetrate the earth's magnetic shield and collide with atoms and molecules in our atmosphere. these collisions result in countless little bursts of light, called photons, which make up the aurora.

auroras are generated by charged solar particles hitting molecules in earth's atmosphere. this usually happens in high latitudes, because our planet’s magnetic field tends to funnel these particles toward the poles. that’s why it can be experienced in northern ohio.