Answer:
7.74m/s
Explanation:
Mass = 35.9g = 0.0359kg
A = 39.5cm = 0.395m
K = 18.4N/m
At equilibrium position, there's total conservation of energy.
Total energy = kinetic energy + potential energy
Total Energy = K.E + P.E
½KA² = ½mv² + ½kx²
½KA² = ½(mv² + kx²)
KA² = mv² + kx²
Collect like terms
KA² - Kx² = mv²
K(A² - x²) = mv²
V² = k/m (A² - x²)
V = √(K/m (A² - x²) )
note x = ½A
V = √(k/m (A² - (½A)²)
V = √(k/m (A² - A²/4))
Resolve the fraction between A.
V = √(¾. K/m. A² )
V = √(¾ * (18.4/0.0359)*(0.395)²)
V = √(0.75 * 512.53 * 0.156)
V = √(59.966)
V = 7.74m/s
Answer:
4 P
Explanation:
V = IR
when they are in series R = 2 r
when they are in parallel R = 1/2 r
so current will increase by a factor of 4 when they are in parallel
and power used will also increase by a factor of 4 to 4 P
Power = IV when I now becomes 4 I power becomes 4 P
You just need the energy of turning of water in to steam. Water is a little funny because once water gets to 100 degrees C, it stops changing in temperature whilst it all turns to steam. The amount of energy required to turn 1 gram of water into steam is 2257 Joules. We call this the latent heat of vaporisation. So to turn 74.6 grams of water to steam, you would need:
2257J/gram x 74.6g = 168,372.2 J = 168.4 kJ
(<span></span><em>latent heat of vaporisation: 2257 J/gram</em>)
Answer:
33 kg m/s
Explanation:
The momentum of an object is given by:
where
m is the mass of the object
v is the velocity of the object
In this problem, the total mass of the child and the wagon is m =22 kg, while the velocity is v = 1.5 m/s, therefore the momentum is
Answer:
u = 5 m/s
Explanation:
given,
Mass of ice skater, M = 45 Kg
initial speed = 0 m/s
mass of the ball, m = 5 Kg
velocity of skater and the ball,V = 0.5 m/s
speed of the ball = ?
using conservation of momentum
m u + M u' =( M + m ) V
initial speed of ice skater is zero
5 x u + 45 x 0 =( 45 + 5 ) V
5 u = 50 x 0.5
5 u = 25
u = 5 m/s
hence, the speed of the ball is equal to 5 m/s
