Answer:
d. 37 °C
Explanation:
= mass of lump of metal = 250 g
= specific heat of lump of metal = 0.25 cal/g°C
= Initial temperature of lump of metal = 70 °C
= mass of water = 75 g
= specific heat of water = 1 cal/g°C
= Initial temperature of water = 20 °C
= mass of calorimeter = 500 g
= specific heat of calorimeter = 0.10 cal/g°C
= Initial temperature of calorimeter = 20 °C
= Final equilibrium temperature
Using conservation of heat
Heat lost by lump of metal = heat gained by water + heat gained by calorimeter

Answer:
sorry i throght i had the answer
Explanation:
44.64m
Explanation:
Given parameters:
Mass of the car = 1500kg
Initial velocity = 25m/s
Frictional force = 10500N
Unknown:
Distance moved by the car after brake is applied = ?
Solution:
The frictional force is a force that opposes motion of a body.
To solve this problem, we need to find the acceleration of the car. After this, we apply the appropriate motion equation to solve the problem.
-Frictional force = m x a
the negative sign is because the frictional force is in the opposite direction
m is the mass of the car
a is the acceleration of the car
a =
=
= -7m/s²
Now using;
V² = U² + 2as
V is the final velocity
U is the initial velocity
a is the acceleration
s is the distance moved
0² = 25² + 2 x 7 x s
0 = 625 - 14s
-625 = -14s
s = 44.64m
learn more:
Velocity problems brainly.com/question/10932946
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Answer:
a) Acceleration is zero
, c) Speed is cero
Explanation:
a) the equation that governs the simple harmonic motion is
x = A cos (wt +φφ)
Where A is the amplitude of the movement, w is the angular velocity and φ the initial phase determined by the initial condition
Body acceleration is
a = d²x / dt²
Let's look for the derivatives
dx / dt = - A w sin (wt + φ)
a = d²x / dt² = - A w² cos (wt + φ)
In the instant when it is not stretched x = 0
As the spring is released at maximum elongation, φ = 0
0 = A cos wt
Cos wt = 0 wt = π / 2
Acceleration is valid for this angle
a = -A w² cos π/2 = 0
Acceleration is zero
b)
c) When the spring is compressed x = A
Speed is
v = dx / dt
v = - A w sin wt
We look for time
A = A cos wt
cos wt = 1 wt = 0, π
For this time the speedy vouchers
v = -A w sin 0 = 0
Speed is cero