It is false, the particles of the medium move perpendicular to the way the wave is going.
Since the amount of matter does not effect average kinetic energy, it must have a higher average kinetic energy. (b)
Answer:
(a) 10 nm
(b) 1 Hz
(c) 20 V/m
Explanation
The equation of a progressive wave is given by:
y = Asin(kx ± ωt)
where;
A is the amplitude of the wave in meters
y(x,t) is the displacement in meters
k = 2π/λ is the propagation constant
ω = 2πf is the angular frequency in radian per seconds
The equation now becomes;
y = Asin((2πx)/λ ± 2πft)
(a) Comparing Ey= (20 V/m)sin((6.28x10⁸)x -2πft) with the general equation
(2πx)/λ = 6.28 × 10⁸
λ = 2π / 6.28 × 10⁸
λ = 1.0 × 10⁻⁸ m
λ = 10 × 10⁻⁹ m
λ = 10 nm
(b) Comparing Ey= (20 V/m)sin((6.28x10⁸)x -2πft) with the general equation
2πft = 2πft
f = 1 Hz
(c) Comparing Ey= (20 V/m)sin((6.28x10⁸)x -2πft) with the general equation
A = 20 V/m
This study was aimed at testing the construct validity of the basketball basic motion skills test instrument (ITK GDBB). The research used descriptive method of 3 basketball experts in the city of Cimahi; 3 experts are the expert in basketball. The instrument used was the ITB GDBB developed by Silvy (2019) consisting of top passing, bottom passing, top service, bottom service, chest passing, bounding passing, overhead passing, and leading ball (dribbling). This instrument consists of 76 items that cover 4 domains in basketball, namely chest pass, overhead pass, bound pass, and dribbling. The validity method used the construct validity of different power types. For the reliability method, it used the Kuder Ricardson (KR) and Objectivity analysis. The results of the construct validity analysis of a total of 76 items show that the score is ranged from 0.67 to 1.00. The construct validity value of 71 items in the basketball game is in the high category (= 1.00), 5 items are in the sufficient category, the relativity score is ranged from 0.75 to 0.98, and the objectivity score is ranged from 0.89 to 0.95. The conclusion is that this test instrument can be used as a standardized basic motion skill test for standardized large ball games for validity in basic motion skills in basketball games for grade VII junior high school students.
From km 240 to km 300 there are 60 km.
The time to travel 60 km at 80km/h is t = d/V = 60km / 80 km/h = 3/4 h.
That is 45 minutes. Then the car will arrive at 7:30 + 45 min = 8:15.