Answer:
2 a) it is less dense than the water
2 b) it is more dense than the water
3 a ping pong ball is hollow and less dense than the water so it quickly bounces up to the surface of the water
Answer:
When acceleration is zero (that is, a = dv/dt = 0), rate of change of velocity is zero. That is, acceleration is zero when the velocity of the object is constant. so probably D
Explanation:
D
Answer:
3.6 × 10⁵ N/C = 360 kN/C
Explanation:
Let R = 2.0 cm be the radius of the sphere and q = -8.0 nC be the charge in it. Let q₁ be the charge at radius r = 1.0 cm. Since the charge is uniformly distributed, the volume charge density is constant. So, q/4πR³ = q₁/4πr³
q₁ = q(r/R)³. The electric field due to q₁ at r is E₁ = kq₁/r² = kq(r/R)³/r² = kqr/R³
The electric field due to the point charge q₂ = 5.0 nC is E₂ = kq₂/r².
So, the magnitude of the total electric field at r = 1.0 cm is
E = E₁ + E₂ = kqr/R³ + kq₂/r² = k(qr/R³ + q₂/r²)
E = 9 × 10⁹(-8 × 10⁻⁹ C × 1 × 10⁻² m/(2 × 10⁻² m)³ + 5 × 10⁻⁹ C/(1 × 10⁻² m)²)
E = 9 × 10⁹(-1 × 10⁻⁵ + 5 × 10⁻⁵)
E = 9 × 10⁹(4 × 10⁻⁵)
E = 36 × 10⁴ N/C = 3.6 × 10⁵ N/C = 360 kN/C
Answer:
B. The force due to gravity is 530 N. The force of air resistance is less than the force due to gravity.
Explanation: