Answer:
buoyant force on the block due to the water= 10 N
Explanation:
We know that
buoyant force(F_B) on a block= weight of the block in air (actual weight) - weight of block in water.
Given:
A block of metal weighs 40 N in air and 30 N in water.
F_B = 40-30= 10 N
therefore, buoyant force on the block due to the water= 10 N
Answer:
The displacement of the spring due to weight is 0.043 m
Explanation:
Given :
Mass
Kg
Spring constant 
According to the hooke's law,

Where
force,
displacement
Here,
(
)
N
Now for finding displacement,

Here minus sign only represent the direction so we take magnitude of it.

m
Therefore, the displacement of the spring due to weight is 0.043 m
Answer:
1.56 J
Explanation:
given,
Spring compression, x = 2.5 cm
Force exerts by the spring,
F = - k x
k = 5000 N/m
Potential energy stored = ?
energy stored in the spring


PE = 1.56 J
Hence, the potential energy stored in the car is equal to 1.56 J.
Answer:
(B) (length)/(time³)
Explanation
The equation x = ½ at² + bt³ has to be dimensionally correct. In other words the term bt³ and ½ at² must have units of change of position = length.
We solve in order to find the dimension of b:
[x]=[b]*[t]³
length=[b]*time³
[b]=length/time³
Wow ! This will take more than one step, and we'll need to be careful
not to trip over our shoe laces while we're stepping through the problem.
The centripetal acceleration of any object moving in a circle is
(speed-squared) / (radius of the circle) .
Notice that we won't need to use the mass of the train.
We know the radius of the track. We don't know the trains speed yet,
but we do have enough information to figure it out. That's what we
need to do first.
Speed = (distance traveled) / (time to travel the distance).
Distance = 10 laps of the track. Well how far is that ? ? ?
1 lap = circumference of the track = (2π) x (radius) = 2.4π meters
10 laps = 24π meters.
Time = 1 minute 20 seconds = 80 seconds
The trains speed is (distance) / (time)
= (24π meters) / (80 seconds)
= 0.3 π meters/second .
NOW ... finally, we're ready to find the centripetal acceleration.
<span> (speed)² / (radius)
= (0.3π m/s)² / (1.2 meters)
= (0.09π m²/s²) / (1.2 meters)
= (0.09π / 1.2) m/s²
= 0.236 m/s² . (rounded)
If there's another part of the problem that wants you to find
the centripetal FORCE ...
Well, Force = (mass) · (acceleration) .
We know the mass, and we ( I ) just figured out the acceleration,
so you'll have no trouble calculating the centripetal force. </span>