The most exact answer is 78.4J also in this kind of options we can say answer "d"
The statement is false. Balanced forces can NOT change the speed OR direction of an object's motion. (See Newton's #1 law of motion.)
Answer:
a)
1.35 kg
b)
2.67 ms⁻¹
Explanation:
a)
= mass of first body = 2.7 kg
= mass of second body = ?
= initial velocity of the first body before collision = 
= initial velocity of the second body before collision = 0 m/s
= final velocity of the first body after collision =
using conservation of momentum equation

Using conservation of kinetic energy

b)
= mass of first body = 2.7 kg
= mass of second body = 1.35 kg
= initial velocity of the first body before collision = 4 ms⁻¹
= initial velocity of the second body before collision = 0 m/s
Speed of the center of mass of two-body system is given as
ms⁻¹
Answer:
<u>954.4m/s</u>
Explanation:
For a free falling object,it has constant acceleration and a changing velocity.
By using the velocity-time formula, the velocity can be obtained.
The height the rock travelled is the distance.
From,
Velocity (v) = Distance (d) / Time(t)
v = 3245m/3.4s
v = <u>954.4m/s</u>
That js the answer I got. Hope it's right.
Density of copper: 8,9
Density of steel: 7,7
Density of aluminum: 2,7
And
Resistivity of copper: 1,7
Resistivity of steel: 16,9
Resistivity of aluminum: <span>2,7</span>
Hope I Helped You!!! :-)
Have A Good Day!!!