Answer:
1/8
Explanation:
17,100 years is 3 times the half-life of 5,700 years. After each half-life, half remains, so the amount remaining after 3 half-lives is ...
(1/2)(1/2)(1/2) = 1/8
1/8 of the sample remains after 17,100 years.
Answer:
887.1Hz
Explanation:
Given parameters:
Speed of sound wave = 330m/s
Wavelength = 0.372m
Unknown:
Frequency = ?
Solution:
To solve this problem, we use the expression below:
Speed = Frequency x wavelength
330 = Frequency x 0.372
Frequency = 887.1Hz
Answer:
The angle of incident ray is 40°.
Explanation:
Given that the angle of incident and reflected ray are the same. In this question, we had given that both angles added up will gives you 80° so you have to divide it by 2 :
incident + reflected = 80°
Let incident = reflected = θ
θ + θ = 80°
2θ = 80°
θ = 80° ÷ 2
= 40°
Answer: a) vcar= 7 m/s ; b) a train= 0.65 m/s^2
Explanation: By using the kinematic equation for the car and the train we can determine the above values of the car velocity and the acceletarion of the train, respectively.
We have for the car
distance = v car* t, considering the length of train (81.1 m) travel by the car during the first 11.6 s
the v car = distance/time= 81.1 m/11.6s= 7 m/s
In order to calculate the acceleration we have to use the kinematic equation for the train from the rest
distance train = (a* t^2)/2
distance train : distance travel by the car at constant speed
so distance train= (vcar*36.35)m=421 m
the a traiin= (2* 421 m)/(36s)^2=0.65 m/s^2
Answer:
Number value and direction
Explanation:
Vectors are quantities that can be identified by value and direction . Examples are velocity and acceleration