Answer:
The velocity of the truck after the collision is 20.93 m/s
Explanation:
It is given that,
Mass of car, m₁ = 1200 kg
Initial velocity of the car, 
Mass of truck, m₂ = 9000 kg
Initial velocity of the truck, 
After the collision, velocity of the car, 
Let
is the velocity of the truck immediately after the collision. The momentum of the system remains conversed.




So, the velocity of the truck after the collision is 20.93 m/s. Hence, this is the required solution.
Answer: mass = 48.47 kg.
Explanation:
Formula : Weight = mg , where m = mass of body , g= acceleration due to gravity .
Given: Weight = 475 N

Substitute all values in formula , we get

Hence, his mass = 48.47 kg.
Answer:
10 db
Explanation:
Detailed explanation and calculation is shown in the image below
Answer:
t = 4.58 s
Explanation:
In this problem, we need to find the time elapse between seeing lightning and hearing the thunder if the lightning strikes 1mi (5280 ft) away and the air temperature is 90.0°F.
T = 90.0°F = 32.2 °C
The speed of sound at temperature T is given by :
v = (331.3 +0.6T)
Put T = 32.2°C
So,
v = (331.3 +0.6(32.2))
= 350.62 m/s
We have, distance, d = 1 mile = 1609.34
So,

So, the required time is equal to 4.58 seconds.
Answer:
Explanation:
You don't do the same amount of work. The work formula is F*d = W
W = work
F = force
d = the distance moved.
So you do more work when you move the 10N object because the Force (F) has doubled.