Answer:
a. 8p
Explanation:
We are given that
Radius of hollow sphere , R1=R
Density of hollow sphere=
After compress
Radius of hollow sphere, R2=R/2
We have to find density of the compressed sphere.
We know that


Therefore,
Volume of sphere=
Using the formula



Hence, the density of the compressed sphere=
Option a is correct.
Answer:
The forces acting on the pen which is still on the table can have two forces acting on them. The forces are gravitational force and the equal and opposite force to the gravitational forces.
The equal and opposite forces that is applied on the pen keeps the pen still on the table.
So, the statement that no force is applied on the pen which is kept still on the table is wrong as two forces are applied on the pen.
As both the forces are equal and opposite so it is cancelled and is still.
Answer:
Acceleration=4m/s²
Force applied =619.8N
Explanation:
Using equation of motion
V=u+at we have: u=o, v=50m/s
50= 0 + a×0.0121
a = 50/0.0121
a= 4m/s²
Neglecting resistance forces
F= ma, where a = v-u/t
F=m×(v-u)/t
F= 0.150 ×(50-0)/0.0121
F=7.5/0.0121
F= 619.8N
True it’s true because in the book it said all that stuff
By calculating the crests, you can find the waves' frequency.
Hope this helps!