Answer:
t₂ = 3.89 s
Explanation:
given,
speed of car = 23 m/s
speed of motorcycle = 23 m/s
after time of 4 s distance between them is equal to = 53 m
motorcycle accelerates at = 7 m/s
time taken to catch up with car = ?
let t₂ be the time in which motorcycle catches car.
distance traveled by car in t₂ s
d = 23 t₂ + 53
distance traveled by motorcycle
using equation of motion


now, equating both the distances


t₂ = 3.89 s
time taken by the motorcycle to catch the car is equal to 3.89 s
The correct option is B.
Sunglasses are designed to block polarized light. If you are driving toward the sun, most of the sun's glare will be coming to you horizontally, thus, the best sunglasses to wear is the one, that will block the horizontal glare and allow only the vertical glare to pass through.
Answer:
The temperature rises by 0.52K
Explanation:
Detailed explanation and calculation is shown in the image below
Answer:
C. Just measure the volume of the container it is in
Explanation:
Another why of measuring the volume of gas is by filling a contractor with water then in invert a glass jar air will miss place the space taken by water then measure the volume of water misplaced to get the volume to air
Answer: V = 15 m/s
Explanation:
As stationary speed gun emits a microwave beam at 2.10*10^10Hz. It reflects off a car and returns 1030 Hz higher. The observed frequency the car will be experiencing will be addition of the two frequency. That is,
F = 2.1 × 10^10 + 1030 = 2.100000103×10^10Hz
Using doppler effect formula
F = C/ ( C - V) × f
Where
F = observed frequency
f = source frequency
C = speed of light = 3×10^8
V = speed of the car
Substitute all the parameters into the formula
2.100000103×10^10 = 3×10^8/(3×10^8 -V) × 2.1×10^10
2.100000103×10^10/2.1×10^10 = 3×108/(3×10^8 - V)
1.000000049 = 3×10^8/(3×10^8 - V)
Cross multiply
300000014.7 - 1.000000049V = 3×10^8
Collect the like terms
1.000000049V = 14.71429
Make V the subject of formula
V = 14.71429/1.000000049
V = 14.7 m/s
The speed of the car is 15 m/s approximately