True
Most photographs will be made using a shutter speed of 1/60 or faster.
Answer:
a) 4.98m/s²
b) 481.66N
Explanation:
a) Using the Newtons second law of motion
m is the mass of the object
g is the acceleration due to gravity
Fm is the moving force acting along the plane
Ff is the frictional force opposing the moving froce
a is the acceleration of the skier
Given
m = 60kg
g = 9.8m/s²
= 35°
Ff = 38.5N
Required
acceleration of the skier a
Substituting into the formula;
Hence the acceleration of the skier is 4.98m/s²
b) The normal force on the skier is expressed as;
N = Wcosθ
N = mgcosθ
N = 60(9.8)cos 35°
N = 588cos 35°
N = 481.66N
Hence the normal force on the skier is 481.66N
Answer:
D.vibrations that cause changes in air pressure
Explanation:
Sound is a type of wave.
A wave is a periodic disturbance/oscillation that trasmits energy without transmitting matter. There are two different types of waves:
- Transverse waves: in a transverse wave, the direction of the oscillation is perpendicular to the direction of motion of the wave. These waves are characterized by the presence of crests (points of maximum positive displacement) and troughs (points of maximum negative displacement). Examples of transverse wave are electromagnetic waves.
- Longitudinal waves: in a longitudinal wave, the direction of the oscillation is parallel to the direction of motion of the wave. These waves are characterized by the presence of compressions (regions where the density of particle is higher) and rarefactions (regions where the density of particle is lower). Examples of longitudinal waves are sound waves.
Sound waves, in particular, consist of vibrations of the particles in a medium - most commonly, air - that occur back and forth along the direction of motion of the wave. Because of these motion, the air will have areas of higher pressure (which correspond to the compressions), where the density of particles is higher, and areas of lower pressure (which correspond to the rarefactions), where density of particles is lower.
Gas because liquids and solids volumes don't change from switching containers.
