Answer:
Vf = 75.4 m/s
Explanation:
In order to find the final velocity of the penny when it would hit the ground, we will use the equation of motion. In this particular case the third equation of motion can be used. The third equation of motion is written as follows:
2gh = Vf² - Vi²
where,
Vf = Final Velocity of the penny when it would hit the ground = ?
Vi = Initial Velocity of the penny = 0 m/s (Since, the penny starts from rest)
g = acceleration due to gravity = 9.8 m/s²
h = height of building = 290 m
Therefore,
2(9.8 m/s²)(290 m) = Vf² - (0 m/s)²
Vf = √(5684 m²/s²)
<u>Vf = 75.4 m/s</u>
Answer:
Ví dụ 1 : Hai vật xuất phát từ A và B cách nhau 400m chuyển động cùng chiều theo hướng từ A đến B. Vật thứ nhất chuyển động đều từ A với vận tốc 36km/h. Vật thứ hai chuyển động đều từ B với vận tốc 18km/h. Sau bao lâu hai vật gặp nhau ? Gặp nhau chỗ nào
Answer:
361.46 N
Explanation:
= Coefficient of thermal expansion = 
Y = Young's modulus for steel = 
A = Area = 
= Original length = 1.28 km
= Change in temperature = 
Length contraction is given by
Also,
The tension in the wire is 361.46 N
Answer:
The position of the spring in terms of g, m & k is 
Explanation:
Stiffness of the spring = k
Mass = m
When a mass m is attached with the spring then spring stretched. in that case the force exerted on the spring is equal to weight of the mass attached.
⇒ Force exerted on the spring F = k x
⇒ m g = k x
⇒
This is the position of the spring in terms of g, m & k.
