Given:
m(mass of the box)=10 Kg
t(time of impact)=4 sec
u(initial velocity)=0.(as the body is initially at rest).
v(final velocity)=25m/s
Now we know that
v=u+at
Where v is the final velocity
u is the initial velocity
a is the acceleration acting on the body
t is the time of impact
Substituting these values we get
25=0+a x 4
4a=25
a=6.25m/s^2
Now we also know that
F=mxa
F=10 x6.25
F=62.5N
Any type of physical act isn’t a emotional reaction. Things like crying or yelling or getting mad at yourself is emotional. Changes in your activity level, change in eating, sleeping, sense of humor. Increased uses in tobacco or drugs, when you’re becoming accident prone, when you’re not able to relax, when your heart rate increases, headaches, startled easily, when you’re tired all the time and sleep doesn’t help (fatigue). For women your period might change. When you get lower back pain, upset stomach, flare ups that are associated with allergies asthma or arthritis and if you get sick easier. If you lose more hair than normal for your body. If you’re blood pressure is up. Things like this is physical. You might find people will isolate themselves or blame themselves. They may have a difficulty concentrating. You can look up so many ways that stress can affect a person physically
The meters per second
+1t a second / 2t
f' = frequency observed by the police car after sound reflected from the vehicle and comes back to police car = 1250 Hz
f = frequency emitted by the police car = 1200 Hz
V = speed of sound = 340 m/s
v = speed of vehicle = ?
frequency observed by the police car is given as
f' = f (V + v)/(V - v)
inserting the values in the above equation
1250 = 1200 (340 + v)/(340 - v)
v = 6.9 m/s
Answer:
FALSE
Explanation:
The answer is false.
The speed of the sound in water is faster when compared to the speed of sound in air. This is because, the particles in air is loosely packed and are far from each other as compared to water or liquid.
The water particles are close to each other than air particles, so water particles are able to transmit the vibrations of the sound faster than the air particles.
Therefore sound waves travels faster in water than in air.