F = ma
6.25 N = 0.4 kg · a
a = (6.25/0.4) m/s² since N=kg·m/s²
a = 15.625 m/s²
The answer is c) 15.6 m/s²
(Note that the mass of the soccer player is irrelevant.)
(a) 
The frequency of a wave is given by:

where
v is the wave's speed
is the wavelength
For the red laser light in this problem, we have
(speed of light)

Substituting,

(b) 427.6 nm
The wavelength of the wave in the glass is given by

where
is the original wavelength of the wave in air
n = 1.48 is the refractive index of glass
Substituting into the formula,

(c) 
The speed of the wave in the glass is given by

where
is the original speed of the wave in air
n = 1.48 is the refractive index of glass
Substituting into the formula,

Answer: 114 km/h
Explanation:
The formula for determining average speed is expressed as
Average speed = total distance/total time
The car travels 85 km in the first half hour of a trip. The car continues to travel for 2 more hours and travels 200 km. It means that the total distance that the car travels is
85 + 200 = 285 km
The total time spent by the car is
0.5 + 2 = 2.5 hours
Therefore,
Average speed = 285/2.5 = 114 km/h
Answer:
If one cup falls down then there will be 59 cups left.
Answer:
The tension is 
Explanation:
From the question we are told that
The total mass is 
The radius is 
The density of air is 
Generally the upward force acting on the balloon is mathematically represented as

=> 
=> 
Here V is the volume of the spherical helium filled balloon which is mathematically represented as

=> 
=> 
So

